That was a hundred pounds of play sand. And since my tank is so established I don't get much poop on the bottom. The cichlids do most the work. The plants like it too. I do the same thing as Alasse and skim the top when I overfeed to make em grow faster lol. The red jewel there has tripled in size in 1.5 months HBH spirilina cichlid gold frozen brine frozen blood worms frozen salad and spirilina flakes is all I feed em.