Most inverts are going get ate in a trigger tank.Large Brittlestars will eat detritus, but they may get chomped on here and ther.Possibley a very large hermit might survive ,but doutful.small crabs and snails will get picked apart even in rock work do to the triggers mouth shape.algae eating fish might be an option,but alo could be snaks as well,Do you use a skimmer on the tank.The only one that really works: water changes, nutrient control, etc.