Quote Originally Posted by stangchris View Post
do you have ball valves on your overflow and return i have a 65g with a internal overflow its an AGA but i think the overflow is the same, i had to dial down the return a lil to eliminate bubble and gurggling noise, also by dialing it down the over flow fills a lil higher and the water fall noise goes away.thats a pic of my tank and sump.

The overflow looks like mine but I dont have the ball valves. The waterfall noise in coming from the sump, Here is mine.IMG_1299.jpg