That one is a 125 but I've done similar aquascapes in my 55 as well. I just recently changed to a sand substrate and the fish seem happier for it. I add a few taller plastic plants to help break up sightlines in the tank that will help if there is an aggressive fella in there. He don't chase what he can't see. The fish seem to like sifting and moving around sand, depending on what types you keep. Mine like it though. If your keeping peacocks some get more vibrant color on lighter substrate and backgrounds while others will get brighter against a darker substrate and background. In the end just go with what tackles your fancy though.