How many serpae tetras can I put in a 20 gallon long with 11 panda cories? And how many black skirt tetras could I put in another 20 gallon long with 6 peacock gudgeons? My grandfather picked out the three tetras without knowing they need to be in schools, and now I'm trying to make them as happy as possible, and I know they don't do well in small numbers.
I would do 8 serpae tetras and 7 black skirts. You would be at just about full stock, but the proper filtration is also needed for them to be healthy. What filters are you running on them?
I have two sponge filters in each tank, a 20 gallon + a 10 gallon filter in one tank, and the same setup in the other.
