I'm keeping 12 Nannostomus marginatus in an 8 gallon (8in tall and wide 30in long). Previously i had 14, but I did a decor switch and added a bunch of oak leaves. This unfortunately basically caused a re-cycle, and I definitely lost 2 fish to dropsy. The re-cycle happened during finals week so I may have lost other fish. I just did a recount and only got 11 but I could have missed one (they're so Darn fast). Is there room for any low bioload fish besides a restock of marginatus? I'm thinking along the lines of a solo or small school. Maybe there are tetras that will school with marginatus?