Hello! First post on this forum, so please don't judge harshly My husband is in a process of setting up a 65 g tank that will eventually become a discus tank. We just set it up last week, started cycling, bought the plants and... screwed it up. I left our nearly 3 year old near aquarium without supervision and she started playing with the magnetic cleaner and sure enough - the glass is now scratched. Some scratches are just barely visible, some are deep enough to feel with the fingernail. We read about using cerium oxide and wool pad to buff the scratches out (yes, i know, very hard to do and could be impossible on the deep ones). But here is a trick question - even if we manage to buff the scratches out, would this tank be safe for discus? Could even the trace amounts of cerium oxide harm the fish? If anyone who keeps discus could share their experience that would be greatly appreciated.