Trying to rescue my red claw crabs

[Goldy]

Bought 2 red claw crabs today to put in my freshwater 10 g. Have since realized they do best in brackish water. I was considering getting a marineland eclipse three and turning it into a brackish crab enviroment. How much salt should I put in 3 gallons of water and where should I put it (the filter?)? Any advice would be helpful.

[OrionGirl]

For a brackish setup, you really will need a hydrometer to accurately determine the specific gravity. Salt is not all created equal, so the amount to use can vary with the type of salt, humidity, etc. You'll need marine mix--table salt will not work.

Also, make sure there is access to the surface--these crabs need to get out of the water and breathe.

[wheresmyloach]

Red claws do not have to have air. Fiddlers do not rcc. I have had them and they do fine in water. You can have air if you like and they will go up there but they will do fine in water.

[RTR]

Red claw crabs, somewhat less than fiddlers, are not, repeat not, submerse aquatic crabs. Both require air access, but the fiddlers do need essentially full-time emerse with water access, while the red-claws are less demanding.

[cdawson]

agreed, fiddlers spend very little time in the water. Just because you've kept them fully submerged for a short period without issue doesn't mean it works. Come back here when you've kept them in those conditions for several years without losing one every few months. They breathe AIR not oxygen from the water, they cannot get that in a fully submerged environment.

[RobUK]

If they breath air rather than air from the water wouldnt it only take them a few mins to suffocate or am I being dense?

[cdawson]

They can take oxygen from the water column but just barely enough to stay alive for short periods of time.
Besides in most aquariums they can find some way to reach the surface. I've seen them shimmy up the silicon in the corners to make it out.

[Snake Eyez]

I hope you have better luck than I did with the RCC. I bought 5 of them and they slowly died over a period of 3 months. And they are very clever at finding ways to get out of the tank. The last crab was missing for a day and I finally found him inside the housing of my filter. He had climbed up the intake tub and squeezed inbetween the housing and the lid of the filter.

[boiceboy]

I'm not sure if you even need brackish conditions. I've had my RCC for several months now in fresh and he has molted twice (so I'm thinking that means he is healthy and growing). I am constantly checking the tank to make sure he hasn't escaped though, he is so FREAKING CLEVER!

[cdawson]

A couple months is nothing, when you've kept them for 2 years then you can talk. Depending on how much dissolved content and the calcium levels it may last a significant time. However, it's immune system is lowered and jeopardized by being away from the beneficial minerals and buffers in marine salt.