Thanks Dan, This is what I have, 90g pent corner tank with a center pent shaped overflow box with two returns and two drains in it, I think there 1" bulkheads. I am running a mag 12,in sump, with three maxjet 900 powerheads in the tank. The tank came with these slotted pipes,like the ones Herbie uses, that where covered 1/2 in sponge, the water level in the overflow box was about 3 inches with these pipes so the drop was about 26", Niagara Falls sound. The tank height is 30", I made my 2 dursopipes 29" and the first thing was the water level came up above the elbow just below the caps, and there was this large flushing sound that happened very frequently and I could not get the water level to stay constant it would ride and fall. I had started my durso cap holes very small and went up to a 1/4 with no change in the sound. So then I just removed the caps and still no change. Then after reading several threads here at reefcentral I noticed my drain hoses had many dips and loops so I changed thoses out as well. I tried to use flexible pvc but the constraints of space and the sump can not fit directly under my drains, I couldn't use the pvc and I had to cut and splice my original drain hoses that resemble vacum cleaner hose.
My first question is can I use Herbies method in my overflow box and my second question with my setup is where to start? I am struggling I guess with where to begin on my system. What size pipes do I use? I looked at Herbies pics and I wish I could see how he has it plumb into the bulkheads. Where does his return lines go? Please forgive my ignorance on this. I am tring to read everything I can on reefing but am struggling with a time issue right now with family and work, any free time is with wife and kids so that leaves me late nights only. It took a year just to get RODI water into my tank. I like to do things slow and right the first time. LFS is really no help with this. Being in the medical field I can save your life with what I know but reefing is much more complex than that. Thanks for any help.