Recently I broke down my old 5 gallon betta tank and upgraded (cloned it) into a 20 gallon long. One of the things I am interested in is getting a few more fish in this tank. However I'd like advice on what people have had success with and what people advice to stay away from.
Here is a picture of the tank:
There will be a better light that sits in a nice hood come Sat once I get it back from someone. The water is soft, and the substrate is Eco Complete Plant Substrate.
I am running a kind of a sponge filter that I put together to one side:
A few people and I have talked and we seem to agree that this probably is functioning as a sponge filter thought the original intent was to control the bubbles so I have a circulation that doesn't bother/stress my Betta. I will be getting new black cardboard to put on the back of the tank. I am using what was on the 5 gallon till I get more.
There are multiple plants in this tank as I prefer to keep planted tanks. There is Hydro Willow, Cabomba, Water Sprite, Riccia, Java Moss, Water Wisteria, Red Ludwegia, and even two little Cuban Ludwegia bits I rescued from the big tank when they snapped off the parents.
So that's the basics of the tank. One of the things I'd like to potentially put in is a school of Harlequin Rasbora. I am aware you do not want any fish that have trailing fins or is very colorful sharing space with a potentially aggressive betta.