I have a 56 gallon set up as salt and I just cant get it right So before I get in way over my head financially I'm thinking about switching over to fresh, namely I was planning on having a "rock" part and a "sand" part (whole substrate will be sand actually). I want to do shell-dwellers, and maybe some yellow labs or others that I find will work with shellies (hard to match them up due to size differences). Anyway is there any use having a sump with bioballs or maybe gravel ? Also, I know certain plants will work, especially with the shellies (like anubias etc). The tank is 24" tall, and I have a 175 W MH light, is that way beyond overkill?