New take on heating and lighting ideas for hermit crabs

Guest · Post by **Guest** » Fri Dec 10, 2004 4:29 am

I have been reading many posts here and on other sites regarding heating and lighting for hermit crabs. It has lead me to rethink heating for hermit crabs and expermient with different methods of heating and ultimately to change heating recommendations I make personally to new crabbers. First of all, some hermit crab books discourage lighting for hermit crabs for fear it will "dry them out". This should not happen if it is done properly. Lighting can be beneficial to hermit crabs, giving them a more natural day/night cycle. Also, if the proper lighting is selected, it can improve color rendering, which can be important in the selection of foods and in other natural behaviors as well. Phillips has a lighting line you can get at home depot. I got their daylight simulator fluorescents-- 48" and 40 watts each for about $6 each. They provide a natural daylight lighting for my hermit crabs during the day. They also assist in warming the tank. As for heating, many depend on UTH's and stay away from radiant heat sources like incandescent bulbs or ceramic heat emitters for fear again that this will "dry" them out. There are many other tropical species of animals that require high humidity and people have been properly lighting and heating them for years using fluorescent lights, incandescent lights and/or ceramic heaters. This should be no different for hermit crabs. The ideal range for our little buddies is reported by most sources to be about 75-84 deg F. Hermit Crabs, like reptiles and amphibians are "ectothermic", i.e. they do not produce their own body heat and thus rely on their environment for their body temperature. Proper body temperature is critically important for proper digestion and other natural biological functions in hermit crabs. Chronic exposure to temperatures below this range is less than ideal and probably detrimental to the crabs. A word about UTH's: They give you a warm spot, but do little to heat the air in the tank. They can also get too hot under the substrate and possibly harm a hermit crab that burrows to molt, or more ironically, one that burrows to cool off! I am not saying it is a bad idea necessarily to have a UTH, but keep in mind you should have a rheostat or thermostat to modulate the temperature so that it doesn't get too much above 85 deg F at the bottom of the substrate. Overhead radiant heat sources are far more efficient at heating the tank for the same or lower wattage it would take in UTH heating, and they are easier to control with thermostats and/or rheostats. ESU has a nice combo light fixture available in 20", 24", 30", 36" and 48" with 1 fluorescent fixtures and 2, 3 or 4 incandescent fixtures (safety ceramic fixtures rated up to 150 watts each). It also has another VERY important feature that other combo lights do not have. It has 3 separate power cords so that you can independently control day light, day heat and night heat with separate timers and/or thermostats!As for the type of fluorescent lighting you get for your hermit crabs, UVB is somewhat of an unknown for consideration with hermit crabs. We are starting to learn more about their calcium requirments and other animals with captive calcium requirements have benefitted from UVB lighting to help them synthesize Vitamin D3 to allow for proper calcium absorption. So, is a UVB fluorescent absolutely necessary for hermit crabs? Probably not. Is it harmful-- I don't htink so-- they are exposed to UV in the wild, as some crabs are active during the day, maybe not as much as night activity, but active nonetheless. A nice reptile UVB bulb will give you excellent color rendering. So too will the phillips daylight simulator fluorscent for a lot less money.I think we should move away from UTH's as the staple recommendation for heating of hermit crabs. Reason 1 is the potential danger for overheating if a crab burrows down over the UTH. Reason 2 is that they are relatively inefficient at warming a hermit crab tank, especially a larger one, and they are difficult to modulate properly with a thermostat or rheostat. I believe we need to shift over to systems that allow for overhead radient heating that is easier to control and more efficient at warming the ambient air in the tank. You will still havea warmer area under the heat source an a cooler area away from the heat source, you will just have more efficient and more even warming throughout the tank, which is probably better for hermit crabs. I am still in the process of experimenting with applying a small acryllic approved UTH to a TropicAire Humidifier unit to see if this raise the temperature of the tank. This would be ideal, as the unit could then provide both needed heat and humidity. A brief word about humidity: I have not had any trouble maintaing humidity levels in my tank using different overhead heating methods ( I now currently have the 2 40 watt fluorescent bulbs for the day for lighting and heat, and a 40 watt ceramic mounted inside the tank out of the way for night time heat. I have a 75 gallon tank, which is 48x18x22. You need to select proper wattage for your tank based on the temperature in your home and the size of the tank you are warming. I'll be happy to help people out with recommendations. Just page down and look for post from Jdei Master Thrash and you will find where he makes his rec's. Keep in mind yours may differ based upon the heat in your house and size of your tank.My humidity stays in the mid 70's. Coconut fiber and two large basins of water also assist with humidity levels. As long as humidity levles are monitored and proper adjustments made, people should not fear "drying" their hermit crabs out. Your hermit crabs will probably thank you for nice even warmth and maintenance of a proper temperature range provided by overhead radiant heat that is controlled by a reptile thermostat or rheostat. Here are links to examples of both:Rheostat (2 recepticle, up to 500 watt):Thermostat (3 outlet, up to 1000 watt):I hope this information is helpful. I'll be happy to answer any questions anyone may have.

Guest · Post by **Guest** » Fri Dec 10, 2004 5:36 am

I recently switched to a 48" terrarium bulb which I believe is made by ReptiZoo or something like that... after reading several posts concerning UV lighting, I wanted to be sure my hermits were actually getting all of the best of natural lighting that can be mimicked through indoor lighting. I will definitely say that the hermits are better stimulated to move around a bit during the day and to at least eat more; the science behind that I know nothing about). Beyond that, my colors are much more vibrant and my straws look much more beautiful.I respectfully disagree with the elimination of the UTH, and this opinion comes from my own experimentation. Several weeks ago I purchased the Tropicaire humidifier/air exchanger for my 55-gal. tank. It really works... humidity levels stay anywhere between 70 and 80 percent, and I never have to mist to get levels up. I have hermits of various sizes, from micros to my softball-sized PP, so I have to keep enough substrate so that the depth is enough for my jumbo to tunnel. I use a UTH on the far left of my tank, and about two inches of coconut fiber substrate sits atop this; the rest of the tank is sand and varies in depth from 4–6 inches.Although my tank has a slate bottom which I believes distributes heat from my UTH much better than my previous glass-bottom tank, there is a wide variety of temperatures in the center of the substrate. The coconut fiber hovers from 80–85 degrees, depending on how much moisture is in it. The center of the tank (where the sand is thinnest) stays from 75-80 degrees, but the thicker far end has ranged from 65-75. Most of my Es bury in the cooler end; the PPs in the coconut fiber; the Indos and Ruggies on the second level where the sand is about 70 degrees; and the Straws (when they ever bury and decide to rest after trashing my tank) prefer the colder sand.However, the moisture in the fiber keeps my PPs fickle. If it's damp (not soggy), they love it and I can usually find all of them sleeping together. If it dries out completely, they avoid it altogether and stay in the middle.Beyond that, the Tropicaire will only maintain my tank's "good" humidity if the coconut fiber is moist. Since the substrate's water evaporates as it rests atop the UTH, the air temperature obviously becomes more humid, and as long as the temperature from the bulb above maintains the proper air temperature, all is in perfect order. Mold has never been a problem, either. BTW: I usually mist the top of the coconut fiber with dechlorinated water once a week with about a cup of dechloronated water; the moisture seems to the bottom and the evaporation begins.If one doesn't have such an elaborate setup, especially beginners, the UTH is good for those who just can't keep decent heat from bulbs/screens, as long as the correct heater is purchased in accordance with the tank size. And a UTH should never, ever cover the entire base of the tank since hermits need their cool spots to regulate their body warmth.It could be argued that water will evaporate from my water bowls or that the Tropicaire should be providing the best humidity levels, but I've tried this and it simply hasn't been the case for me.

Guest · Post by **Guest** » Fri Dec 10, 2004 5:42 am

I need to add that I also use two moonlight bulbs for the overnight hours; these provide proper humidity levels at night... and look as cool as heck!

Jedediah · Post by **Jedediah** » Fri Dec 10, 2004 8:33 pm

I have used a 30 watt incadescent blulb in my 20 gallon from the beginning, with a humidity never under 70%. The crabs like to sit next to the bulb and seem to enjoy the occasional sunbath. I use a UTH for the night, but when I set up my bigger tank, I'll stop using it. Either I won't heat the tank during the night or I'll put an UTH on the side of the tank. But I tend towards no UTH.About the UV lighting: does anyone know whether crabs can see UV light, like bees or parrots can?

Guest · Post by **Guest** » Sun Dec 19, 2004 3:58 am

I have a UTH in my tank and the purpose for putting it there is so they have a warm dry sand area which they can go to. On they end of the tank there is only about 2 inches of dry sand, they 2 big water dishes are also on that side for the reason that when sitting over the UTH (about 1 in. of sand between the water dishes and the glass) this ups the humidity greatly I have experimented with the water at both ends and with the water at the end where all the wet sand is the humidity will drop by about 10 degrees!(Normally both temp and humidity are at about 75 degees, the humidity dropped to 65 during that experiment) I have lights above too, regular light on the side where the UTH is also and Moonglo type on the other end both are st up on timers that through trial and error I now have set just the way I want it. I have the glass tops that have the hinged sections larger on the front and a smaller section on the back, I have replace the smaller back sections with screen and the lights are above the back screened sections. In there natural enviroment they have the option of staying in the wet sand or going to the warm dry sand and also to be able to get in the light to warm up or to go to the shade, they also have the evening temperatures that drop slightly. To create this in a crabitat I think it is very important to have both the UTH and the overhead lights which is what I strive for in my crabitat. I also think that one of the biggest issues a newcomer has is the humidity and whatever it takes to get and keep that humidity up will save alot of inocent hermie lives.

Aviate · Post by **Aviate** » Sun Dec 19, 2004 8:54 am

Once Again, I COMPLETELY disagree Bill.Overhead lighting as a sole source of heat for most newbies is a recipe for disaster. For someone without an advanced set up, there are only two settings: HOT and OFF. Incandescent bulbs will dry the tank out and overheat the crabs. This rarely ever happens with a UTH. An fixture which offers UVA UVB daylight flourescent light is great, but thats not what youre suggesting. Again, as I said regarding your filtered basin idea, unless you have a ton of time, constant attention and money to put forth, it is not going to work to have heated lighting as the source of heat. As a supplemental source in winter, if CAREFULLY monitored, sure. But as a sole source? I do not think so. PP and Indo Hermit crabs specifically do not like overhead heat/light. They are quite nocturnal for that reason. However, the ground on which they sleep and travel is well heated as it absorbs warmth from the sun. (Ever put your feet on the beachsand? Its always warm.) I will not be advocating light as a main heat source. It is very touchy if not done perfectly and will much quicker kill your crabs than any UTH ever will.Also, you state you have several HUGE water basins. Well, that would certianly combat the humidity issue that will occur due to the drying out factor of bulb usage. But most people have "normal" sized water dishes, not 2 3 gallon basins.Also: you state: " As for heating, many depend on UTH's and stay away from radiant heat sources like incandescent bulbs or ceramic heat emitters for fear again that this will "dry" them out. There are many other tropical species of animals that require high humidity and people have been properly lighting and heating them for years using fluorescent lights, incandescent lights and/or ceramic heaters. This should be no different for hermit crabs. "this does not take into account that hermit crabs are nocturnal and will hide if there is a stark lighting system on the tank.I personally agree that UVA and UVB need to be researched and considered for hermit crabs. But I do not think removing any UTHs and adding a light kit as a main source of heat is the answer. Many peoples homes are already about 70 degrees. A uth should be suffcient. A huge set of bulbs on a smaller tank will be overkill. I agree with BP Batch totally, there is a middleground, and if youre going to use only one source, UTH is the safer bet. I use BOTH a UTH and a floruescent light hood. The UTH works well -as it should if you get the right sized one for your tank; and my floruescent light hood raises the temp a mere 3 degrees or so, and provides the day/night cycle. There is no need for the incandescent bulbs. Peachy- You have a 20 gallon tank, and your tank ALREADY has the proper temperature, so you wouldnt need to add a light system, especially if your tank has already hard to maintain humidity. It would only make the humidity worse and raise the temperature which doesnt need to be raised since its already perfect.This is what I am saying when I say these methods youre advocating, Bill, dont apply to the general tanks under 50 gallons. Why does she need to go out and spend $200 to fix what "aint broke"? You said:"I think we should move away from UTH's as the staple recommendation for heating of hermit crabs."I have a problem with this statement.Years of research have devoted the Old-time land hermit crab owners, as well as major companies such as Crab Island etc. to advocate and use UTHs. How long have you owner hermit crabs? Long enough to get a real sample group which leads you to make such generalizations? The admins here are concerned that the advice you have been offering lately may be good for advanced hobbyists with huge, expensive set ups (involving 50 gallon or larger tanks, 3 gallon water basins, rheostats, advanced light kits, etc), but do not cater to the average hermit crab owner. That said, it is important that you recognize your audience. Perhaps what you are suggesting is for the top 10% of the crabber population, but we feel it is dangerous at best for it to be pushed for those who cannot do it absolutely perfectly, or who just plain old dont need it, as in Peachys case.You said:" Established crabbers who have figured out how to modulate the UTH in their set up can stay as is. I am just saying for a new crabber, overhead radiant heat may be easier and better."This was possibly the worst statement in your entire narrative. The newcomers are specifically the ones who need the simplest set up while theyre learning. A light bulb kit they have to dish out money for is unnecessary and also a danger. Is EVERYONE going to monitor the temperature and humidity minute by minute and will everyone know what to do if something goes wrong, which it will for a newcomer who has a 10 gallon with incandescent light as the only heat source? This is not sound advice, IMHO. I feel the same way about your statements about not bathing crabs, and filtered water basins, among others... No offense, but since you personally sell all these items and get to test drive them as well, I wonder how objective you are being about their practicality.

Guest · Post by **Guest** » Sun Dec 19, 2004 11:15 am

Bravo well said Aviate.That was some of the points I was trying to get across but could never do so as elequantly.In my opinion no newcomer should try it Bill's way and Aviate thank you for stating the ideas of many of us out here pulling our hair out worrying about those who have gone his route, and the unfortunate suffering of many little hermies.

GSnicklegrove · Post by **GSnicklegrove** » Sun Dec 19, 2004 12:34 pm

UTH's are the safest means of heating crab tanks.1) Since so many newbies bring their charges home in a kk, a UTH may be the only option, as a heat lamp, or worse yet, a ceramic heater on a kk is a fire hazard.2)For children who are responsbile for their crabs set-ups, high wattage heat set-ups are dangerous. Furthermore, many of these same set-ups are in children's rooms. Very unsafe. AT this point in time, hermit crabs are still being marketed and recommended as a good child's pet.3)If you use an elaborate heating set-up, because of circumstances, it will cost a fair dime.4)There is absolutely no studies, and not much word of mouth expereince regarding whether crabs fare better under a high wattage set-up, or with UTH's in a house with central heat. No one, myself included, can say that one way over the other is better or preferred at this time. 5)High wattage heat can only be used on tanks 35-40B or higher. Heat lamps take the humidity from the air. It is important for anyone considering a heating set-up to have first a large tank, and second, the correct supplies like a rheostat, accurate digital thermometers/hygrometers, and a means for generating humidity like huge water basins, bubbler stones and various humidifers and/or drips. We're talking some money here, and even spending all this money, you have to fiddle with it to get the set-up just right for your particular house environment.Additionally, Ceramic heat lamps are generally a lot hotter than any flourescent or moonglow bulbs with equivalent wattage. So youre suggesting the hottest possible bulbs be used, which will generate the most heat. And placing it IN the tank could be deadly. These should NEVER go in the tank. Not only is this a shock hazard, but they cannot be around any water. They are not for high humidity applications.This is not to say there are no ways to do this successfully. There are. IF you keep tropical reptiles, than you know how to keep high heat and high humidity balanced.There are some situations where using heating devices might be called for. I use heating devices, and since I live in a cooler state, and I have vaulted ceilings, my house can get a little on the cool side at times, a little drafty. However, if your house is not drafty nor especially cold, then heat lamps are not only unnecessary, but extremely dangerous.For instance, if you house is 70 degrees, and you use a 40 watt ceramic heater, you may have a habitat spot that is 110 degrees or more. I know. I have kept crabs for quite a while, and also keep a colony of wonderful little reptiles.Heating crab tanks with ceramic heaters is by no means new. Everyone who keeps exotic reptiles knows the whole gig with heat lamps. Heat lamps have been here for decades upon decades, and people who have crabbed for many years are not in the dark. However, people just learning how to keep their humidity up should never mess with a heat lamp. Posting opinions is fine, but there is a fine line that is now being crossed, which left discussion status to "this is the only suitable way" status. Actually, because crabs, tanks, houses and people's states vary so much in temperature and humidity, there is no one perfect way.It has been our (I mean all veteran crabbers) expereince that heating with UTH's is by far the safest and most efficient way to heat crabitats. For people who have trouble trapping the heat of an UTH, make a thread or pm one of the knowledgable members on LHC, we can tell you how to adjust your tank to trap the heat.In closing, there is no evidence other than CIRCUMSTANTIAL there are any benefits using heat lamps INSTEAD of UTH's. UTH's are definitely the safest and most manageable. It's one thing to state an opinion, but as with anything, if there are Pros there are cons. Always ask the cons, before doing anything new to your crabitat, the hermies health depends on it.Gertieedited because a word was censored. sorry gertie!

CrystalStone · Post by **CrystalStone** » Sun Dec 19, 2004 1:21 pm

My opinion: On small tanks, the UTH is the best way to heat it. A crab won't bury himself where he's gonna get cooked. UTH's are designed to only cover 1/3 of the bottom of the tank which provides a gradient where the crabs have a choice to be on the warm side or the cooler side. It is much harder to provide the gradient using a lamp on a small tank. Smaller tanks also dry out quicker.I don't see a problem using heat bulbs on larger tanks(40B or more). I personally prefer heating the air rather than the substrate, alhough I don't agree with using daytime bulbs at all. They are nocturnal. The real daylight in the room the tank is in should be enough to provide a light cycle. The only concern would be a lack of vitamin D3 which is needed to process calcium. I've been giving my crabs a supplement for this(do not try this at home) but haven't seen any significant differences in their behavior as of yet. I'd suggest a moonglow bulb if you really want to go the bulb route. It's much cheaper and provides a nice soft light. Many other nocturnal animals are kept that way without problems.

Guest · Post by **Guest** » Sun Dec 19, 2004 2:20 pm

I gotta agree with gertie, aviate, and others here...Being nocturnal animals, there's nothing natural about heat from above. At night, the ground releases warmth being absorbed during daytime, so there is some heating from the bottom up in nature.Having used quite a number of UTHs and heat bulbs (for reptiles), my opinion is they work differently. Heat lamp tend to be very focused, whereas UTHs with substrate will spread the heat out.Also, UTHs WILL heat the air in the tank. Not to the dramatic extreme with bulbs, but it will heat the inside, my side mounted thermometer consistently show 5+ degrees over the room temperature using only UTHs.

Post by **JediMasterThrash** » Mon Dec 20, 2004 1:33 am

Aviate and others, I do agree with your point about newbies vs. advanced. For a new crabber with a small kritter carrier, thin gravel, and no humidity, moving to sand, UTH, water bowl with sponge, and covered lid is the quickest, easiest way to dramatically improve the livelyhood of the crabs. This is the basic information I put in my care sheet.However, for someone who wants to provide the best possible care for their hermit crabs, they need to go beyond that. Sure, overhead heat might not work well in a small 10g tank, and you can't fit large water basins. But the problem here is not the light or the water. The problem is the tiny tank. I posted my thoughts on this on this thread already:http://landhermitcrabs.com/eve/forums?q ... 5151&p=2So, as said, I agree with the points by both Bill and Aviate. I agree that the best is what we should strive for, but practical reasons prevent many people from achieving this, so the recommendations given space and money issues will be different than those for someone without those issues.But, I still find several quotes to be incorrect.quote:Originally posted by Aviate:Incandescent bulbs will dry the tank out and overheat the crabs. In a tiny tank without adequate moisture, yes it will dry them out. But this blanket statement is incorrect, and we've been reproving that it's wrong again and again. Low-wattage incandescent bulbs do not overheat the crabs. The ideal range for crabs is 75-85o. I have 50w in my tank, and the temp doesn't get above 75o. And for any size tanks, it is possible to provide adequate moisture to prevent the tank from drying out. A mere 15w of light heat is not going to dry out the tank significantly more than 15w of UTH heat. They both dry the tank out via the same mechanism. Moisture escapes into the air. The air heats and escapes out the top of the tank, taking the moisture with it. Quite frankly, even a large basin of water alone isn't enough to keep up the humidity. You really need moist substrate to do this. The sand/coco-fiber around the water bowl should be moist (the crabs will probably do it anyway, and they'll probably moisten many other areas). This moist sand/coco-fibre maintains moisture extremely well, and this is what keeps the humidity in the tank, and it does so far better than just sponges in a water dish. Even a small 10g can have 3 inches of moist coco-fiber, and the humidity will probably stay at 80% even with 15w of light.quote:But as a sole source? I do not think so. Again, depends on the tank and your house temperature situation. Low-wattage light is the sole source of my, and several other crabbers', tanks. And it works for us far better than UTH did (granted we have larger tanks, but again, the statement is too broad).quote:PP and Indo Hermit crabs specifically do not like overhead heat/light. They are quite nocturnal for that reason. However, the ground on which they sleep and travel is well heated as it absorbs warmth from the sun. (Ever put your feet on the beachsand? Its always warm.) This is absolutely not true. My PPs climb right up to the top of the cholla under the moonglos and enjoy the warmth. My big indo barely comes out at night or day, so I can't say much about him, but my small indo is out during the day playing with all his ruggie friends. The "light" issue is solved by having a moon-glo/night-glo. But I remember a post by someone a while ago saying that when they added a new 5.0 UVA/UVB light, the crabs absolutely loved it. They might enjoy sunlight more than we realize (especially without predators to worry about). Any time during the day I can walk by my tank and see at least half a dozen crabs out doing acrobatics. And when I check on my crabs in the middle of the night (when all the jumbos come out to play), it's clear that the moon-glo bulbs don't inhibit their nightcrawling activities.You second point actually proves the case for lights. It is the overhead light which warms the top layer of sand on the beach. But next time you're at the beach, did down a few inches. The sand below the surface is cooler, and the farther you did down, the cooler and moister the sand. This is the natural way. Crabs bury to cool off and to find moisture. In nature, they never bury to get warmer.quote:I will not be advocating light as a main heat source. It is very touchy if not done perfectly and will much quicker kill your crabs than any UTH ever will. I've heard many stories of crabs burying down over the UTH and dying. Or getting stuck in the sand which "bricks" over the UTH. I have previous posts where I talk about the bricking effect, which is a result of wet sand under pressure drying out and bricking in the same process as real bricks/sandstone are created. I have never once seen a post where someone had crabs die from overhead lighting.quote:Also, you state you have several HUGE water basins. Well, that would certianly combat the humidity issue that will occur due to the drying out factor of bulb usage. But most people have "normal" sized water dishes, not 2 3 gallon basins. As I mentioned above, water basins are for self-bathing, not so much humidity (unless you have a bubbler/waterfall which disperses humidity very well). It is moist substrate that really keeps the tanks humidity.quote:this does not take into account that hermit crabs are nocturnal and will hide if there is a stark lighting system on the tank. That's why any day-lights are turned off at night. Nobody ever said to leave daylight bulbs on 24-7. Just keep the moonglo bulbs (or ceramic heat emitters) on at night, which don't affect their nocturnal behavoir. But if we keep the crabs in the dark 24-7, this will definitely affect their day/night cycle. I don't see any reason not to give them some extra light during the day, which they would have on the beach, but might lack in a house. And as I stated before, my crabs are well adjusted and happy, and enjoy being out playing during the day. Light doesn't scare crabs, it's shadows that scare crabs (reminds them of predators swooping in from above).quote:But I do not think removing any UTHs and adding a light kit as a main source of heat is the answer. Many peoples homes are already about 70 degrees. A uth should be suffcient. A huge set of bulbs on a smaller tank will be overkill. I agree with BP Batch totally, there is a middleground, and if youre going to use only one source, UTH is the safer bet. Again, depends on the tank. There's no way my tank could be heated by UTHs. Many peoples homes are in the mid to low 60s during the winter. We should tank a poll on that, but I'd bet it is. Every winter there's tons of posts by people asking how to keep their crabitat warm during the winter when the house is kept much cooler. It's been proven that a UTH alone is insufficent with houses below 65o. Also, some research from Bill suggest crabs may be much better off in temps above 75; 70o might be too low for long-term health. And some crabbers have their crabitat temp raised to around 80o during the day, and report the crabs enjoy it much better. Remember, the crabs live on the equator, where it's probably over 100o during the day. They bury and hide under cover to cool off, but they know how to deal with it, and are used to it.I agree that a

huge set of bulbs on a small tank may be overkill. But you can find incandescent hoods at the thrift store or grage sales for a couple dollars, and get some low-wattage moonglos at a pet store for 5$. This isn't overkill.As for "UTH is the safe bet", again, there's no evidence yet of lights ever harming crabs (though granted they've mostly been used by people with larger tanks), but there are reports of UTHs possibly harming crabs. Especially when they bury to molt over the UTH. When I had a UTH in my 55g, all my crabs did their burying and molting on the cold side of the tank. They never enjoyed burying over the UTH. As stated before, the natural instinct of crabs is to bury to get cooler and to find moisture. Not to get warmer.quote:I use BOTH a UTH and a floruescent light hood. The UTH works well -as it should if you get the right sized one for your tank; and my floruescent light hood raises the temp a mere 3 degrees or so, and provides the day/night cycle. There is no need for the incandescent bulbs. Flouresent lights can be around 15-25w as well. This is the same wattage as a low-wattage incandescent bulb. Flourescents are more efficient at converting that energy into light, but it still represents a comprable amount of heat dissipation.quote:You said:" Established crabbers who have figured out how to modulate the UTH in their set up can stay as is. I am just saying for a new crabber, overhead radiant heat may be easier and better."This was possibly the worst statement in your entire narrative. The newcomers are specifically the ones who need the simplest set up while theyre learning. A light bulb kit they have to dish out money for is unnecessary and also a danger. Is EVERYONE going to monitor the temperature and humidity minute by minute and will everyone know what to do if something goes wrong, which it will for a newcomer who has a 10 gallon with incandescent light as the only heat source? This is not sound advice, IMHO. I have the classic newbie crab setup with my ISO tank. It's a 10g with an UTH. I have to monitor the temp and humidity minute by minute as is, since smaller tanks are so much more difficult to maintain. I don't think crab care would change because you have lights instead of an UTH. The UTH for any crabber without an expensive rheostat is also an "ON" "OFF" only heat source. Except that crabs can come directly into contact with it, unlike with the lights.I have 2 bowls, one with salt and one fresh, each with a sponge. I used to have 4 bowls. Took up all the room on the left side, but even with four bowls, it was impossible to keep up the humidity without bi-daily misting. But now I realized that I just need to keep the lower substrate moist, and the humidity magically stays above 70%. I finger small deep depressions into two corners, and pour salt water into them. The water slowly soaks into the lower substrate, and keeps the tank humid far more efficiently. I have no problem keeping the substrate moist even with added lights, and this keeps the humidity up easily.UTHs are expensive. You'll easily spend 20-40$ depending on the size. You can find a light hood for a few dollars used, and the lights themselves are 5$ apiece. My lights are been on continuous for THIRTEEN MONTHS (!!!) without burning out. I've heard several stories of people's UTHs dying on them. And with a UTH, once you stick it on, it's STUCK! You can never reattach it to a different tank, and it's a hoot to remove it. As far as electricity cost, the 10-25w for the UTH is the same as the 15-25w for a light.I gaurantee that if you keep the lower substrate moist (which is something I highly recommend anyway, since crabs dig down to find moisture, and they need moist substrate to molt), you'll have no problems keeping up humidity, whether with a 15w UTH or a 15w light. And there's no way you'll overheat your crabs with just a 15w light. quote:Years of research have devoted the Old-time land hermit crab owners, as well as major companies such as Crab Island etc. to advocate and use UTHs. How long have you owner hermit crabs? Long enough to get a real sample group which leads you to make such generalizations? I just started doing my 3rd deep clean yesterday after 5 months. I had only 1 crab death over the whole 5 months, and it was one of the new cavs I just bought last month.My 30+ crabs who've been with me for 16 months with 2x25w moonglos as the only source of heat are still alive and healthy. Only 5 maintank deaths over the course of a year, all of which were explained by mold or bad molts. My crabs are active during the DAY, and perform acrobatics on a regular basis. At any given point in time there's at least 2 crabs down having successful molts. With this kind of success, how can I NOT excitedly recommend my crab keeping methods to others?

Post by **JediMasterThrash** » Mon Dec 20, 2004 2:00 am

Just to cover a couple other quotes from other posters.Also, a reminder that I do agree with you all, that care recommended to beginners should sometimes be different than best/advanced care. I just feel a couple of these statements weren't entirely correct, or were too much of a "blanket" statement, and I don't want to discourage people with the time and money to try out some new ideas.quote: From GSnicklegrove: "high-wattage heat..." I'm not sure where high-wattage heat got into the discussion. I've always advocated low-wattage heat. In my table, I only recommend 15w for 10g.Though, for my "advanced" tank, I'm thinking of moving up to higher wattage. I think the crab will be happier with temp around 80 than around 75. And I just bought two tropic-aire humidifiers (they're only 6.99 at petsmart, and one was open-boxed, so I got it for half price), and i have two waterfalls (one fresh, one salt), and I'm changing to moist coco-fiber/sand mix. I don't think I'll have any trouble keeping my humidity above 80%!quote:Frome GSnicklegrove: For instance, if you house is 70 degrees, and you use a 40 watt ceramic heater, you may have a habitat spot that is 110 degrees or more. I know. I have kept crabs for quite a while, and also keep a colony of wonderful little reptiles For reptiles, don't you usually place the heat emmitter in the tank though? That's something we never recommended for crabs, for that exact reason. There would be spots over 110o. I have 50w of lights in my tank, and even at the top of the cholla under the lights, it's no more than 80-85, which is still within the ideal crab temp range. I don't think you have to worry about putting the crabitate over 80-some degress with low-wattage lights outside of the tank.quote: From CrystalStone: A crab won't bury himself where he's gonna get cooked. This has been proven wrong enough times. Crabs have burying themselves over the UTH, and died. Thats why we always say to never put heat rocks or mats in the tank, becuase crabs will sit against them and cook. First, never overestimate the intelligence of a hermit crab second, they don't sense heat the same as we do. They don't necessarily know what's too hot or not, just what their body tells them. Kind of like how their eyes are different from ours. They can sense light/shadow and motion for sure. But we're not sure about color or pattern recognition, and they probably don't have any depth perception.quote: From Thamster: Heat lamp tend to be very focused, whereas UTHs with substrate will spread the heat out Maybe with a targetted heat lamp, but the the exact opposite is true with heat lights in a hood. The light reaches all parts of the tank, and heats all the air and surfaces evenly. UTHs on the other hand heat just the substrate above them. The substrate on the other side of the tank is cool, as is the air in the rest of the tank.

CrystalStone · Post by **CrystalStone** » Mon Dec 20, 2004 3:26 am

quote:Originally posted by Jedi Master Thrash: quote: From CrystalStone: A crab won't bury himself where he's gonna get cooked. This has been proven wrong enough times. Crabs have burying themselves over the UTH, and died. Thats why we always say to never put heat rocks or mats in the tank, becuase crabs will sit against them and cook. First, never overestimate the intelligence of a hermit crab second, they don't sense heat the same as we do. They don't necessarily know what's too hot or not, just what their body tells them. Kind of like how their eyes are different from ours. They can sense light/shadow and motion for sure. But we're not sure about color or pattern recognition, and they probably don't have any depth perception. But...most crab owners are using UTH's with problems being few and far between. The average crab seems to have proven himself smart enough to regulate his own body temp and remove himself from where he will suffer from the heat. As with everything else in this world, there are always exceptions. I think it was bpatch that said he uses slate tiles over his UTH. This is an excellent idea for anyone who is worried about cooking their crabs. It eliminates the hot spot and distributes the heat more evenly.I am totally, 100% against using daytime bulbs on the crab tank. My own crabs hide from daylight in the darkest part of the tank in caves or under plants. Sure, there is always at least one of them wandering around at any given point of the day, but for the most part, they are in back sleeping and hiding from the light. I'd take this as a big tipoff that they don't like it. In the evening when it gets dimmer in the room, they all come out and about and are as active as can be. I don't have any heater on my tank at all now. I keep my home at 75* all year round plus about 1/3 of the tank is above the baseboard heater which gives them a nice 80* corner in the tank if they should get chilly. I do not see any problems with using moonglow bulbs in a larger tank for those who need extra heating. I use them with a couple of my other critters and I love them. It's a nice soft radiating heat. You have to be sure that the basking spot(using lights there will always be a basking spot) doesn't exceed 85*(I personally wouldn't go above 80*).I think it's great that there are so many of us crabbers who are continually trying to improve crab care.

Post by **JediMasterThrash** » Mon Dec 20, 2004 3:39 am

quote:Originally posted by CrystalStone:But...most crab owners are using UTH's with problems being few and far between. The average crab seems to have proven himself smart enough to regulate his own body temp and remove himself from where he will suffer from the heat. As with everything else in this world, there are always exceptions. I think it was bpatch that said he uses slate tiles over his UTH. This is an excellent idea for anyone who is worried about cooking their crabs. It eliminates the hot spot and distributes the heat more evenly. I agree, hermit crabs do show signs of being able to regulate their temperature pretty well. I stated myself that my crabs old dug on the cold side, so they must have enough abilities to know where the warm and cold substrate is. But I was joinst pointing out cases of crabs doing dumb things like burning themselves on heat rocks or buring ontop of the UTH. I don't really know where their intelligence and abilities begins and where it ends.Also, some members have placed a layer of gravel over the UTH before putting the sand ontop of it. I think this helped prevent bricking.quote:I am totally, 100% against using daytime bulbs on the crab tank. My own crabs hide from daylight in the darkest part of the tank in caves or under plants. I haven't used any daytime lights yet. Just moonglos. I just remember the post where someone tried out the new 2.0 or 5.0 UVB/UVA daylight bulb, and reported the crabs flocked to be under it. I found a flourescent fixture at the thrift store for a couple dollars, so I'm going to try it out and report my findings. Direct sunlight rarely reaches my tank, so even during the day when they're active, it's not full daylight-light. So I'm doing to need more research on the issue.quote:I keep my home at 75* all year round Uff-Da! I break a sweat standing at 72o! You must not be from Minnehsotah.

GSnicklegrove · Post by **GSnicklegrove** » Mon Dec 20, 2004 3:50 am

Jedi Master Thrash-I think there could be a breakdown of communication here. I don't know how to answer your questions, I don't quite know what you are referring to.None of my responses were in relation to the way you recommend/heat your tank.Since the very first post, not only were daylight heat lamps advocated, but Ceramic heating elements.As I have said before, because I live in Washington state, and my ceilings are all vaulted, and with windows my house is quite drafty naturally, I have a heating set-up rigged on my crab tanks. I never said it can't be used, but I am against the blank recommendation of using them for all people, especially since so many kids and people with tiny tanks are learning.As well, not only have I been diligent over time setting up my heating devices, I have expereimented with them. I also have multiple tanks of reptiles in my house with varying heating devices and habitat specifications. Since I have many ceramic heaters going (even on one crab tank), and since I have used various flourescents and what not for 12 years, these are simply my observations on the issue.The heating methods you have advocated are sensible for lots of people. However, the heating methods mentioned and discussed in the very first post of this thread can only be used with extreme caution. They are not recommended for use by children, nor in a children's bedroom, where so many crab tanks, close to children's beds are located.One last note, while there are ridiculously expensive reptile slider hoods for sale that include a ceramic socket for a ceramic heating element, I would not choose to use it on a crab tank, for many reasons. Any other mounting of a ceramic heating element inside a crab tank is dangerous and against manufacturer safety recommendations.As well, not all reptile slider hoods come with the ceramic socket for ceramic heaters, so if someone goes this route, they must get the right sockets for the right heat lamp.Anyway, Jedi, I actually quite agree with your all your methods of crab keeping....my post was in more in response to the initial post in this thread. For people who do not know better, there is a difference between daytime spots, desert UV bulbs, moon glow, infrared, black lights, and the full blown heavy duty ceramic heating elements. The corresponding wattage between some of these heaters can produce various degrees of heat. It is possible to use any of them, though, I agree, I have experimented greatly in that regard.On one last note, Crystal STone is right. The biggest danger with UTH's is turning them on in the fall, when a crab may be buried already for moult. Crabs thermoregulate themselves.Plenty of people who are not sure about how to set up some heating devices properly (like high wattage stuff) burn and kill their reptiles every year. There is no one best heating technique, as people's crabitat needs vary.Gertie