I'm thinking about getting a 20 gal. in a month or two so I can put all of my clowns and the pleco together, and possibly with some dither fish. Just a stop on the journey up to my 100 gallon! I've never had substrate in my tanks yet because I was advised to hold off on it when I first started "fishing". What do y'all recommend for substrate? I've heard good things about both sand and gravel. Sand will help with the pleco poop, whereas gravel makes vacuuming easier. Whichever one I choose, I want brown or black as the color.