So whenever I transfer my fish to their big aquarium I was wondering how long I could keep the fish in a 55g while I get the new aquarium ready. The 4 fish that will be in the 55 are a 14" tire track eel, 12" sun catfish, 11" polypterus endlicheri and an 8" malabaricus hoplias. I plan on doing a quick seeding with established filter media and running established filters that were used on the 55g tanks. Of course I'll do daily water changes if needed to keep ammonia at bay.