I have a 20 gal long with 3 guppies and a pair of mollies in it and i was wondering what the max population limit should be with them. it looks empty with just the 5 fish. i know they will be reproducing very quickly
well, you could ad some danios, as they are perfect for a long tank, as they swim a lot. you could maybe get 4 or so cory cats, and also add some live plants, that will fill up some space. personally, i would leave it at that.
you could add more live bearers i would add danios since they love to eat little frys you could always add tetras neons, black neons, or cardinals would be good hatchets would do well also