Crabs turning purple
When I put my crabs in my tank thier shells were a sandy brown colour, now they have turned purple, matching the colour of some of my live rock. Is this normal ?
what should I do ?
__________________
Starting fresh ... 90 gal, 40gal sump, sundial T5HO x 4, 2 x koralia 2's, ASM G1X skimmer 
|