mine have been settled in the same spot and haven't moved from the sand bed.. low flow, moderate/low light..
I feed Mysis and oyster eggs twice a week.. the tank also gets fed rotifers and phyto, but that doesn't do much for them
I have sexy shrimp that hang around them, have had plenty of amphipods until recently with no ill effects
they have thrived in my tank, and it really is a pretty dirty tank by reef standards
mine are about 2", so no reproduction yet.. there are some great articles on nano-reef if interested