So I don't really know what changed but rescently I have ben having isues with keeping both sides of my sump with equal flow. \n \nSo this is pretty much how the piping is set up with a couple 90s on each side to go tords sump. \n \n[URL=http://s291.photobucket.com/user/CivicDemon07/media/Saltwater/sump2.png.html][IMG]http://i291.photobucket.com/albums/ll318/CivicDemon07/Saltwater/sump2.png[/IMG][/URL]\n \nMy problem is if I have the valve on the left where the refugium is on fully open then the refugium side gets massive flow and the sump side gets really low flow, I close it off a bit and then I can equal out the flow, but it seems that after some time bubles build up on the valve and the flow then reduces on the left side and start going way more on the right side. So I don't know if maybe drilling a hole on the left side before valve would help with some air line to clean any bubles. Or maybe you guys have some tought ons the issue. With the silenser for the overflow where it uses a cap and hosing to silence it work to reduce bubles and give me better flow ???