I have had several [I]Nymphoides aquatica[I] start to do very well, with five large floating leaves to date. The oldest, about five weeks or more, is disintegrating much in the manner of "crypt melt". The stalk and the lower leaves are okay.
I did remove a Nerite snail about three weeks ago, which was boring a hole in the leaf. Perhaps this was the beginning of irreversible damage. If other possible causes or contributing factors come to mind, I'd appreciate comments.
Should I cut off the leaf or should I take the whole stalk?