We have a small (I think Hill stream) loach in our tank with two goldfish. For the last few days I’ve not seen the loach which isn’t necessarily unusual as he is quite elusive so not thought much of it. I thought I’d have a quick look for him this evening only to find him upside down stuck under a rock. I moved the rock and he just sank on his back. His feeders underneath and his eyes were moving but the rest of him wasn’t. I’ve since noticed he’s moving his fins but his dorsal fin hadn’t moved. He’s now sat on a rock the right way up but isn’t doing a great deal. Do they burrow at all? I can’t believe this is normal. Any ideas?