Hello, I recently purchased a 1.5 gallon neon tetra tank and three neon tetras. Shortly after my purchase as I was researching how to take care of my fish I realized my tank was much too small for my fish to live happily. I am going to purchase a 20 gallon and introduce at least 3 more neon tetras and maybe two dwarf guorami would that be too much for a tank of that size? Also if that is proper stocking could a pleco or chinese algae eater be added?