Red claw crab help

[Jerryisepic]

Hi! I recently, maybe a month ago got 3 red claw crabs, recently one has died but the other two are doing great, however they both have this white chalky outline on them, I thought at first they were just gonna molt but they haven’t yet, they weren’t like this when I got them, they’re currently in freshwater, I’m trying to get salt to make it brackish, but the ph balance is good and they have a filter and land and everything, could someone please tell me if this is normal or if they’re sick or something

 

[Waterbabe]

Aquatic marine sea salt you need, but dont pour it in with out diluting it first as it will kill them. You've done well to keep 2 without too many fights or limbs lost as they are very very territorial and need more than 10 gallon at least each in space. If it is molting you can see a slit crack on the head begin to start, and leave the outter shell in there, they will enjoy eating it for the calcium. Is the diet varied? Are they having lots of vegetation too? Is the water warm? Do they have heaps of hiding places?

 

[Jerryisepic]

Hello, sorry it took me so long to reply, ive just ordered some marine salt and a heater for them, I give them daily fish flakes and dried river shrimp and cucumbers and veggies when I have them, my smaller crab likes to hide under rocks and in a little ball cat toy I put in there and my bigger one basically lives in a little hut I made for them on the surface. Is there any specific way I should add the salt to the water once I get it? They’ve lived in freshwater their whole life

 

[Donya]

I don't see anything that looks chalky/strange in the pic. Are you referring to the lighter coloring in the groves on the back?

Is there any specific way I should add the salt to the water once I get it?

Offhand I don't know the exact salinity red claw crabs need. However, I have kept other animals that were sold to me in freshwater that needed brackish and had to be changed over gradually. I would mix the amount of salt you need for your tank at marine strength in a small bucket with an air bubbler or powerhead and let sit circulating overnight. You may have some precipitate at the bottom in the morning if you're using tap water (be sure to use water conditioner if so), but but that's fine in this case I think. Add the mixture slowly and in small volumes (like a cup at a time) in an area of active flow over the course of several days, checking the salinity as you go and also keeping an eye on ammonia. You might want to lower the waterline a bit before you start the process. You will need a hydrometer or refractometer to check (refractometer being better). The ammonia testing is because the change in salinity can cause a mini cycle in some cases.

 

[Jerryisepic]

Hello, a little update about my crab situation, I added the salt and heater to their water and it seems o have made them a lot happier! Yay! And my bigger one just did his first molt! Double yay! However it seems to have been a bad molt because his claw broke off in his exoskeleton