I also used to have a 4ft tank, had it filled with neon tetras, marbled hatchetfish, tiger barbs, albino cats, cherry rasbora, gouramis, angel fish, silver mollies, red tail black shark, bleeding heart tetra, siamese fighter, bronze corys, glass catfish, harlequin, spent many relaxing hours watching the fish with the big light off and some mellow music playing in the background