Crab sick due to chlorine?

[TXcrabby022]

Hi, everyone. My hubby recently purchased, washed and boiled a couple of new shells in tap (chlorinated) water and gave them to our crabs. I was glad to see his excitement (so far he's mostly ignored the crabbies), but wish he'd checked with me on the water first! One of the crabs moved in to one of the shells, and now he's acting strange. He's been hanging out near the salt water dish, sometimes digging but mostly sitting kind of hunkered down and not moving much for long stretches. I'm worried that even though the shells were dried before they were put in the tank, he's gotten a bit poisoned. If so, is there anything I can do to help him? He's been acting funny for the last few days, since the switch. I'm especially worried 'cause this was kind of how our most recent tank addition acted before he died. I've answered the template questions to give you some background, in case it could be something else.

1. What kind of substrate is used in your tank and how deep is it?

Play sand and coconut fiber, about 50/50, and about 3 - 4 inches deep.

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?

I have a hygrometer but my temperature gauge has detached from the tank. Our house is about 77 degrees F in the daytime and 72 at night. Tank temperature is probably around 75, maybe a bit higher near the UTH on the back side of the tank. Humidity ranges between 45 and 80; I keep the substrate moist and mist a few times a day, but I am planning to replace the lid with a plastic or glass one. In the meantime, I am going to partially cover it with packing tape.

3. Is a heat source used in the tank? If so, what?

Yes, UTH on back side.

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)?

Fresh and salt water are distilled with trace minerals added. I've been using sea salt, though I have stopped and am switching to aquarium salt.

5. What kinds of food do you feed and how often is it replaced?

I give them fresh food daily, including things like bakes sweet potato, applesauce, fried egg, eggshell, lettuce, avocado, banana, bread, peanut butter, and coconut flakes, plus HBH "Variety Bites" and All Living Things "Food Medley".

6. How long have you had the crab and what species is it, if known?

About a year, PP.

7. Has your crab molted, and how long ago did it happen?

Yes, about a month ago.

8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?

10 gallon aquarium with wire mesh lid that is partially covered in daytime with a towel and completely covered at night with towels and plastic lid from a storage tub (both to maintain humidity and keep the cat from removing the towel).

9. How many crabs are in the tank and about how large are they?

2, about 1.5 - 2 inches across the front when they are sitting. Medium?

10. How many extra shells are usually kept in the tank, if any?

2 - 4, rotated.

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

No.

12. How often do you clean the tank and how?

I haven't cleaned the tank in months, but I take out old food and clean up the poop regularly, plus wipe down the walls.

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

No.

14. Has anything new been added to your crabitat recently?

Just the new shells.

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 bathing, occasionally crabbies get to roam around a bit, but they seem to be stressed out by this, so we just try to provide new shells and move the climbing toys around to keep them interested. Also feed a variety of fresh foods.

[StarWarsHermitCrab]

Your temperature and humidity are to low.
The temperature should not be lower than 75 degrees,
and to keep your hermit crabs happy and active the temperature should be 80 degrees.

The humidity shouldn't be lower than 70% or the hermit crabs will die.

Substrate should be six inches deep.

[TXcrabby022]

Thanks, StarWarsHermitCrab. Working on those issues.

[CallaLily]

I guess it's possible it is the problem but these symptoms could also be a sign of impending molt. Just be sure to offer plenty of clean, dechlorinated freshwater and saltwater. I think he'll be ok as long as he has the option to rinse out his shell and proper conditions for molting. Your salt mix should be a brand made for saltwater aquarium use, like Instant Ocean for example.

[wodesorel]

Any chlorine or chloramine would have been gone if the water evaporated. Especially if it was chlorine - that would have been gone the minute the water started boiling. Honestly, for my own crabs, I never dechlor the water I boil their dirty shells in.

[TXcrabby022]

Thanks, Callalily and Wodesorel! I guess it could be time for another molt, especially now that he has his big new home. It is getting harder to find shells for these growing guys! Definitely time to deepen the substrate before they start digging again.