The sealant is a polyurethane, food safe one from our local hardware, $28 gallon, they didnt have the smaller size in, no pics but will be, the priciest part to me was the bulkheads, for their size, the sump is a rubbermaid stock tank from the feedstore, 75 gals, I think around $65 , it has a small tote , in it, 8 gallons, of live sand that the water comes into from the frag tank, then out , through bottom holes,there is a LOT of chaeto in it, and a submerged pump sitting in a fenced in area pumps the water back to the frag tank, pretty simple, no skimmer, there are also some frags in the tank with sprigs of plants started on them. Some free floating caulerpa there also . Water comes into the tank through a spray bar of pvc. Two MHs 4' apart. A very simple system. Water depth stays right at 15", BB, grows softies mostly .