I have a urchin that every time I see it has one of my zoas is they eating it or he placing somewhere else. Wat should I do replace it I have algee in my tank
Do you mean the urchin is picking up polyps and carrying them around?
I don't have an urchin, but if so that sounds 110% like expected behavior. You could try gluing the polyps down with gel super glue
They can come off the frag. urchins will move many things. you could try to offer it shells or something 3d printed to carry. they are shy and think its cammo. Mine mostly sticks to macro algae cammo. I recommend, if you don't want the zoa moved, glue it down, then go get more glue, cuz you're gonna need it.