criter compatability??

Not only are they compatible but they are an excellent mix for clean-up. I have heard however that blue leg hermits are a better choice than red leg, but I don't remember why. I have also heard that some would not have crabs in a reef, but their clean up work is invaluable. I have coral in my reef and the crabs don't seem to do any damage. Additional clean-up critters that could be included in your choices are emerald crabs and brittle stars.
 
Sounds like a good mix. With the extra shells laying around, you'll lessen the chance of the reds killing your snails for their shells. Blues are generally less agressive than reds when it comes to killing/stealing.
 
I have that mix in my tank, except I have scarlett hermits, with zero problems so far. I would add some blue legged hermits to the bunch. My blue legged hermits are invaluable in keeping down the nuisence macroalgaes. I also have an emerald crab, and he has worked very well so far. The general rule is to have one cleaner (snail, hermit, or other) per gallon of water. I have 3/4 this requirement, and find that my clean up crew has a lot of work for themselves. However, they are well fed! ;)
 
I agree about going with scarlets. Mine have never shown an interest in snail shells, and ceriths are prime "real estate." Overall, looks like a good mix.
 
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