It's only a 32-gallon all-in-one BioCube so I was thinking two Nassarius snails and 1 trochus snail and 1 crab. Somebody said you can't put green legged crabs and red legged crabs together oh, is this true?Welcome, and so happy for your excitement. Yes add cleanup crew very slowly the smaller the better. Water to Trochus snails one or two Nasraius , small red legged hermits.
best of luck. Make sure you have a tight lid