crab compatibility

[fishboy444]

I have a 15 gallon(24"x12"x12") freshwater tank that's half filled with water. The occupants are a red claw crab who I've had for 2-3 years. I'm redoing the tank with sand(so taking out the gravel and replacing it) and some new ornaments(driftwood,rocks). The RRC is about 2.5" across leg-tip to leg-tip.Looks like a male because of white pincers but the rest of the claw is sorta bright red and the body dark red.
My question:
Can I add 1-2 more vampire crabs?
If not can I add something else if anything at all?

 

[fishboy444]

would it be okay if I changed all the gravel for sand?

 

[adeebm]

Nope, I think vampire crabs need to be solitary. And they will most likely hunt down and kill your RCCs. They get much bigger than RCCs too. You can add fiddler crabs (like me). They get along okay. Remember to pre soak your sand, or it will float in the tank for ages.

--Adeeb

 

[fishboy444]

Adeebm, are your fiddlers in fresh or brackish?If in fresh how long have you had them in there?

 

[adeebm]

I just got mine, so I'm slowly raising the salinity. They're at 1.002 right now, but I'm going to go to atleast 1.005. RCCs need low end brackish as well and 1.005 should be good for both.

--Adeeb

 

[fishboy444]

okay thanks