I lost one of my stripy angels this morning and have no idea why? I have had him about a year (came with 4 others all were sick and lost the other 3 over 4 days this one survived but his dorsal fin was bent and shorter than normal). I tested the water and my water states are all fine. I have not added any ornaments, plants or fish for ages. All other fish look fine apart from one red eye tetra with a mark on his side (couple of scales missing), but I think that was from squabbling with another tetra.
He came up to top for food as normal and was eating fine (flake) then he suddenly turned to come back for more food and seemed to shake for a couple of seconds then just stopped swimming? by the time he hit the bottom he was dead!! no marks, lesions or anything on the body???
He came up to top for food as normal and was eating fine (flake) then he suddenly turned to come back for more food and seemed to shake for a couple of seconds then just stopped swimming? by the time he hit the bottom he was dead!! no marks, lesions or anything on the body???

or maybe some sort of heart attack as he was rather a greedy fish?, least he died happy stuffing himself.