Can dead plant leaves kill my fish?
It is best to clean dead leaves out when possible as they decay just like surplus food and can lead to an increase in the harmful bacteria of the tank. This of course can also lead to illness in the fish (although I am not sure exactly if that is the problem with your fish at the moment). I would not advise a 50% water change as that will upset the good bacteria but regular 25% water changes should help keep it fresh and clean – like 2-3 times a week until it is sorted. Left-over food can be a problem, you need to make sure you are only feeding the fish as much as they will eat in about two minutes – any more and they will likely become overfed and the leftovers will rot in the tank. To help your fish you may want to buy some melafix from the pet shop. It’s like a cure-all general medicine for fish that should help them return to full health. Good luck.
