[Woodstock]

Looks great! A couple of suggestions... If you plan on having any type of lighting in the sump area, you might want to get black vinyl tubing for the return pump. the clear hose will grow algae inside it and restrict the water flow dramatically.

Also, you mentioned that your son used a few small pieces of your homemade rock in his fw tank and fishes began dieing. It wasn't anything wrong with the rock. It was made for marine fish which require a very high PH. The Fw fish don't. You killed the fw fish when the PH skyrocketed.