This is one of my favorite tanks, mostly because I love the way it looks and there's nothing fancy going on here--just a dual strip NO light, no added gas or liquid CO2, Yamato Green once a week and Flourish Tabs every few months. Substrate is half Flourite, half small natural gravel. A 20 long is a great tank to do low-tech, because the shallow depth means the plants get more light than you would expect, but not enough so that you're compelled to add CO2. You're not going to be able to grow a hairgrass lawn, but you've still got lots of choices. The plants growing above are, left to right, Mermaid weed (proserpinaca pectinata--the green stuff, which is the emersed leaf form), anubias coffeefolia, crypt wendtii, mermaid weed (the submerged form), rotala indica, hygrophila corymbosa, the green in the foreground is three compact swords. Fish: eight corydoras adolfoi, one of the most appealing cories--not that any of them aren't appealing, but these guys are amazingly outgoing and friendly, always out front. They have four ottos for company, which keep any algae under control. By the way, I realize the background looks awful in this picture, not sure why, it doesn't look like that when you're just LOOKING at it.