I am about to set up a 150gal. cichlid tank, how hard is sand to maintain? should I just stick to gravel? and also what kind of filtration is suggested? the tank is acrylic with2 holes in the center of the back on the bottom hidden by a "bump out" ? it will house 2 grown oscars 1 14" pleco, a 10" jag, and 2 4" tinfoils