But if I did 6-8 gudgeons that would probably mean over stocking or no other fish like the peppered cories or snails or the lambchop rasbora...
My advice when anyone asks about stocking is to always attempt to provide the best situation, which includes numbers of the species. The fish will be in better shape, and usually the aquarist will benefit from more interesting interactions. Sometimes I go along with something different, depending upon the circumstances, but pointing out the preferences is giving better advice on the whole.