Mites are little bugs that may crawl all over your hermit crabs and in their cage. According to Christa, mites are about the size of an apostrophe ' and are the color of dried snot (green, or brown, or grey). They run away from the strong light of the sun. They will lay eggs and more will hatch. They are a real problem and can kill your hermit crabs. They are also a real pain to get rid of. If you see any sign of mites, eggs or other pests it is important that you remove it quickly! Some hermit crab owners have been mistaking in thinking the eggs of a larvae fly were tiny hermit crab eggs (they don't breed in captivity). If you see anything other than hermit crabs in your tank it is a PEST and should be removed as soon as possible. It is best to keep a good lid on the tank to keep flies and mites out of the cage and for many other reasons. There is no easy one step solution to getting rid of mites. You must get rid of both the mites on your hermit crabs and in your tank.
Your hermit crab tank is an ideal place for mites to infest because it is dark, warm, and humid and it has food, water, and animals inside of it. Regular cleaning of the tank, bathing of your hemit crabs, keeping the bedding substrate dry, changing food and water regularly, keeping things that attract bugs out of the tank (like cardboard, strong smelling foods, and stuff from outside in nature which may already have bugs on it), and keeping the area around the tank clean and dustless (don't grow plants around the tank, mites are attracted to plants).
You must empty your whole tank and either replace or clean and disinfect (by boiling and baking) your substrate. Also boil and/or bake and/or replace anything else in the cage (except your hermit crabs of course and don't boil sponges, nuke 'em in microwave). Clean the tank very well squishing any bugs you see with the paper towel pressed firmly against the tank(especially in the corners where they hide) and rinsing the tank out very good. Leave everything in the sun for awhile (except your hermit crabs), because mites hate sunlight and will most likely leave the tank if their still in there. Leave the tank upside down in the sun so the mites can easily run off.
The only way to do this is by repeatedly (about 1 or 2 times a day) bathing them in Stresscoat laced water really well. Dechloronated water will work too but you're better off with stresscoat laced. Turn the crab upside down and get ALL the air bubbles out. Then pour the water off the crab. The mites will float to the top of the water and drain out with it. Remove all of the mites from the water by pouring them out, and repeat bathing them. Drain them down the sink, not in the garbage, and rinse out the sink and it's pipes very good afterwards with hot water and soap. Pour the water out before taking your crabs out so that any mites floating on the top don't latch back on to your crabs. Do this a few times until you are sure ALL of the mites are off the crab and out of the shell. You can leave the crab under water for a minute or so, it won't drown and the mites might release themselves. Just be careful and don't leave it under water for several minutes or it will probably drown. You can also use a paper towel and gently squish the bugs on the crab, do this gently though so you don't hurt the crabs or stress them any further.
Sharks unlimited gives advice to bathe the in a Clorox bleach solution. Don't do this, it will hurt your crabs and won't solve the mites problem. Clorox bleach has an extremely high amount of chlorine in it which will blister gills (check water section) and it as other chemicals in it. Also, don't use any mite or bug sprays, hermit crabs are related to spiders and insects. Mite spray will hurt or kill the hermit crabs too.
You may want to only feed your crabs dry food for awhile because strong smelling foods or fresh foods may bring the mites back. Replace the food and water every day. Pay extra attention to keeping the bedding substrate clean by scooping out any poop or buried food and nuke the natural sponges regularly in the microwave.
Mites have a fast reproductive cycle...midges (their babies) hatch and become mites within 3 days...you need to bathe your infected crabs twice a day with a combination of ocean salt water (twice the normal ratio you use for drinking), and then in dechlorinated water with 1 TBSP of stresscoat to 1/4 cup of water... the time you keep them in each solution should be at least 3 minutes, sometimes shorter if they come out of their shell and thus allowing you to flush the water throughout their shell; if they stay retracted, put them upside down (opening up) so water will seep into shell...it is really important that the solution gets into the shell, but if the crab is stuborn or frightened, just note which crab, and try again next time...the salt makes the mites release as they try to avoid salt, and the stress coat has an oily coating which suffocates them.
You need to do this for 3 consecutive days...also, once they have been bathed, give the crabs an opportunity to come out of their shell and see if you can see any mites...these you can try to remove with a q-tip...cleaning your tank is good, but if your crabs still have mites on them, it will end up infested again...I would keep them in a seperate tank from the main one...limit what is in there to things that are not organic (use resin or plastic) Once you have completed the 3 day regiment, observe your crabs closely for at least 3 more days...
If there are no mites present after giving them a regular bath, then all should be okay to return them to the main tank...if there are more mites present, then you will have to repeat the process...It can be hard on the crabs, but it depends on what state of health they are in. You have to use your discretion, as you know your crabs best.
Julia Crab offers this method for dealing with mites.Photo Gallery of Insects and Mites on Ornamental Plants
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