So I didn't want to make a new post and thought I would try to ask a question about my long spine urchin. My tank is a 120 fat boy mixed reef. I currently have 3 urchins in the tank a Halloween, 2 different colored tuxedos. I saw this long spine at petco yesterday and thought that I would add it to my 30 aio fiji cube. I am having a algae outbreak and thought that maybe the urchin would help knock that down. I drip acclimated him for 20-30min and in he went. Let me add that the aio has been up for just under one year (10.5-11months). 24 hrs later he seemed fine. I did notice one spine that fell off. Fast forward another 24hrs later I noticed a couple more spines in the sand bed and noticed that a few of his long spines are laying down. From my experience this is not good. Currently I have him In a small container and I am drip acclimating him to my 120 tank. My question is, once they start losing spines, is it to late, or can they bounce back if the problem/s are remedied? As an emergency fix I am going to put him in a tank with the other urchins becasue I know the other 3 are doing great. Once you notice the spines laying down and a few falling off is it to late or can they bounce back? Thanks. Hope this wasn't wrong for asking this within this post. I figured it would be ok considering they are of a similar questions for the same animal.