I would like to make a shallow crocea only tank. My worry is the stocking density of the clams. Considering the rate that they consume calcium at. The tank I was thinking about is 24 x 24 x 6 , the volume ends up being 15 gallons. Is that enough volume to provide a stable environment for several clams? I wouldn't add fish the tank would have just lr, sand, and a CUC. Lighting was going to be 250 watt MH pendant. Anyone know if this would work?