I have two fiddler crabs, and they seemed to be striving, but now they both seem lethargic. What's going on?

Question

They have brackish water, a place to climb out of, etc, etc. They share a tank with various other fish. The female was hanging out sideways both in and out of the air and water for about 2 days, now she's hiding in some plants. My male has been hanging out sideways too, under the water, and I thought he was dead twice, I checked him out and he moved. Now he keeps "laying" down, but isn't dead? help what is going on?????

I am using aquarium salt for the water, Ive only had the crabs not quite a month. The male lays down, then straightens himself back upright......thank you to the suggestions so far......we can use all the help we can get.

Answer 1

You don't say how long you've had the crabs, or what type of salt you're using to make the water brackish. A marine salt mix would be a better choice for these, since it also contains calcium, iodine, and pH buffers to raise the pH a little. Fiddlers come from areas where freshwater and seawater mix, so these elements are something that;s in their natural environment, and are used in the process of building their exoskeleton when they molt.

When they're molting, the new "shell" is soft at first, so they're vunerable to predators (and each other), so they try to find a place where they can hide until the new shell softens. A pile of rocks in their "land" area, or soft sand or soil where they can burrow should be provided if you don't already have this.

If you've had them long enough to have been through molting and have the proper salt in their water already, consider that these only live for about 2 years in captivity, so yours may just be aging.

Answer 2

are they getting the right nutrients when feeding them? maybe change the water 1/2 and 1/2 old water /new water, fish make ammonia, there may be too much ammonia in the water.

Answer 3

Could be just molting time maybe? Make sure you have trace elements in the water. They need minerals to grow new shells.