HCA: Hermit Crab Association

Since you've come to the emergency forum, we know you want a fast answer to your question. In order for us to figure out the problem as quickly as possible, we ask that you answer the following questions as best you can. Some of them may seem odd, but they're all designed to give us the information we need to give you a good solution for your problem. The things in the [ brackets ] are there to make this post easier to read once submitted. Thanks!


1. What kind of substrate is used in your tank and how deep is it?
Aquarium sand, about 4 or 5 inches


2. Do you have gauges in the tank to measure temperature and humidity? If so, where are they located and what temperature and humidity do they usually read? yes, 60-70 percent humidity, 70-75 degrees


3. Is a heat source used in the tank? If so, what?
Yes, two 4-watt uder tank heaters on the back of tank and the occasional space heater beside it when it gets too cold.


4. What types of water are available (fresh or salt) and how is the water treated (what brands of dechlorinator or salt mix and what ratio is used to mix it)? Salt water is distilled water treated with All Living Things Hermit Crab Soaking Salt, and a seperate dish of distilled water


5. What kinds of food do you feed and how often is it replaced?
A mixture of Florida Marine Research hermie food, All Living Things Variety diet food and eggshells. It is changed every few days. I know fresh food is best, but they do not eat it and it molds witin a day. They seem to love the store bought food. I hate that they dont eat the freah stuff, beause I know its best for them. They seem very uninterested in anything besides what i feed them.


6. How long have you had the crab and what species is it, if known? i have has my four crabs for a year.


7. Has your crab molted, and how long ago did it happen?
Right now two are molting and the other two are not, i will elaborate on this at the bottom, its complicated


8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?
A 10 gal glass tank with mesh screen covered 3/4ths of the way with plastic wrap


9. How many crabs are in the tank and about how large are they?
4 PPs, two about the size of a clementine, one about half that size, and one a teensy bit smaller.


10. How many extra shells are usually kept in the tank, if any?
at the moment, 3. They all recently changed and grew out of the medium sized ones.


11. Have there been any fumes or chemicals near the crabitat recently?

no

12. How often do you clean the tank and how? I spot clean daily, and do a deep clean whenever all four are up and not molting. In the year i have had them that has hapeed once.


13. Are sponges used in the water dish? If so, how are they cleaned?
yes, I boil them

14. Has anything new been added to your crabitat recently?
no


15. Is there any other information you would like to share that might be helpful (anything that is regularly part of your crab care, playtime, bathing, etc.)?
no

16. Please describe the emergency situation in detail. I have had a sudden spring up of gnats in my tank. I did a full deep clean and sand change about 4 months ago. I have two crabs in the main tank molting. Narmally they all molt at different times, and one is usually always under, and they all four do fine in there together. About 3 days ago I noticed a few gnats in the tank but didnt think much about it. They are multiplying quickly, and i think they are fungus gnats. I put a homeade, crab safe fruit fly trap in the tank ad it isn't working. They are multiplying very fast. Do I dig up my molters to do a sand change and deep clean and risk them stressing and dying? or do I leave them and risk their safety and health by letting the fungus gnats stay but not digging up the molters? Just a note: I removed everything from the tank I could and washed it, I left food and fresh water in case one comes up. I made an emergency isolation tank for my two nonmolters and bathed them in case there were gnats in their shell. What do I do??

.

I can't help with the gnats problem, so hopefully someone with experience in that area will chime in!

I do have a few suggestions for improving your crabitat.

I am not familiar with 'aquarium sand', but wonder if it is safe or not. Substrate needs to be at least 6 inches or 3x as deep as your largest crab, whichever is deeper. It needs to be moist enough to hold it's shape. Most of us use a mixture of play sand and EE in about a 5 to 1 ratio.

Your humidity needs to be higher. The play sand and EE mixture helps with humidity. Also putting saran wrap over the entire top of your tank will help; they will get enough air when you change food etc.

That brand of salt will not provide the minerals that crabs need long-term. And I am not sure about using distilled water. Here's the link to the HCA info about water:
http://www.hermitcrabassociation.com/ph ... 27&t=92553

Hermit crabs need protein and calcium daily. They need a varied diet. Here is the HCA info about commercial food and why it is not safe:
http://www.hermitcrabassociation.com/ph ... 25&t=92555

Here is the link about nutrition:
http://www.hermitcrabassociation.com/ph ... 25&t=92554

HCA recommends 3-5 extra shells per crab. Check the shells section for info about proper shells to buy.

If you have proper substrate, deep cleaning is not needed unless there is a serious problem like a bacterial bloom. Spot cleaning is all that is needed.

Sponges are not needed in the water, and only serve to harbor bacteria.

Thank you for this info, super helpful! Do you think the gnats could be a result of a bacterial bloom?

Gnats show up because there is humidity and food, usually something the crabs have dragged off, but it can just be moist cocofiber or moss.

If they are fungus gnats then a fruit fly trap won't do anything. Try cutting a potato in half and putting it cut side down onto the substrate, the larvae will burrow inside and can be removed the next day. It might take several tries to make a dent. Adults are attracted to the color yellow and they do make yellow sticky traps without pesticides for them, but these should not be used around above-ground crabs.

Awesome, will do! Thanks so much!