I have a Juwel 180L. The top cover for the filter is detachable by a finger sized hole. Me and the children have been unwell this past week and I havent paid as much attention to the tanks as usual. Yesterday I noticed that the cover had come off somehow (I assume I didnt put it back tightly enough last waterchange) and was upright behind the plants at the back of the tank. Stuck in the hole was one of my adult female gold barbs. When I finally got her out she had massive trauma to her body, mainly her top and underneath where all the scales had been rubbed away. I was going to euthanise her but decided to dose her with antibacterials and antibiotic. This morning she had scepticemia, lots of red streaks and fungus. So sadly she has gone. Two of the other barbs have minor scrapes so I assume she was unlucky. It obviously was irresistable to the barbs. Am sad (and feeling guilty ) she was one of my first ever fish; one of only 3 I have ever named. Not quite sure why I've written this, other than maybe as a warning.