as mentioned, I made structures from eggcrate and put the black spray foam on it.
than in front of the structure I have a 3/4 inch PVC pipe with 1/5 inch holes drilled into it., in total there are 4 induvidual pipes that all come up in the corner of the tank and are conected to a 4way splitter that is conected to a 1500GPH pump.
so when everything was in place I put my sand in the tank, and placed 1 row of rock on top of the PVC pipe and along the spray foamed structure.
there is a picture where you se the resolt afterwards (you can se what is rock and what is foam.
the PVC pipe on the bottom of the rock I use to fluch debris that might have gathered between the rock, so about each other day ore so, I fluch one zone for about 30 minutes, and than a day ore 2 later I flush the other.
not that it is needed, but I thought it was a need thing to put in, I dont se it, and it douse exactly what everyone recomends to avoid (debris build up)
I have more pic's if needed
