I am currently cycling a 20 gallon tall tank with 6 serpea tetras. I was wondering if I could add a pleco, maybe a clown pleco, to the tank after it is done cycling. I've done a lot of research and most sites say they can live a 20 gallon, but never specify if it has to be tall or long. They are also one of the smaller species, only reaching 4 inches, so would the tank be large enough? There are currently 2 pieces of bogwood in it and assorted fake plants. The substrate is Caribseas eco-complete