Hi everyone.. we are fairly new to this (had our tank for a bit more than 6 months now). Yesterday, we found our urchin on the sand upside down, so I did a quick Google search and found that someone recommended to flip him back over, so we did and he went on his merry way. Today, I found him once again upside down on the sand, and this time, 8 of his spines/legs (?) had fallen off. Up until this weekend, he has been quite active on the rocks and the glass (can't recall ever seeing him on the sand), and we've had him for at least 3 months. For reference, I've attached a picture of him to this post; he's looking a little droopy imo. Any feedback is greatly appreciated. My husband had a saltwater tank years ago, but he didn't have an urchin, so we are flying a little blind here. Thanks in advance!