fish safe

got a couple these while picking up a Walt Disney and some Goni corals. want to add them in the sump and or main display but didnt like they were more attached to the corals base and skirt area. what do you guys think. add to the free clean up crew or sump

First off not a reef question but i love the website Great people on here! So I had a old pre Drilled 110 tub hanging around and decided to fill it for some baby koi Im getting on Tuesday and the treads on the gasket were a bit chewed up and it was leaking. I didn't have tape on me the other...