Its very quiet, all you hear is a slight trickle of water in the drain pipes. Its just basically a modified LFS setup. Most of them just hace the strainers straight in the back oc the tank or a 90* elbow. I tried it first with the strainers pointing up but it was noisy with the water flowing up and over the elbow through the strainer. So I just turned everything and now the strainers are constantly submerged and I have a durso setup behind the tank so everything is underwater and there is no toilet noise at all. I saw a setup like mine but with a 1" pvc straight across connecting the two drains, one he had it with holes drilled in it to let the water in, the other he had cut a slot out of the pipe to make a full length drain across the back of the tank. I was gonna do that if my setup didnt work but it seems to be working fine, strainers can be removed for easy cleaning if need be. The plumbing inside the tank in not glued so I can just lift it up or drop it down to adjust the water level. I think with the 45* fittings before the strainers pointing them down into the tank it makes the angle of the fitting the water level control point if that makes any sense. I also crossed the drains at a 45* angle accross the back of the tank to help with noise, hoping the water would flow down the pipe rather than falling and splashing if it was just a straight down drain.
Rock is very stable, the Marco rock is great for stacking. It locks together really nice and is very stable.
Shane.
