Ziggy953
Aquarium Advice Addict
Interesting solution to a noisy problem. I may have to give the up thing a try. And you are right you would need to make a "U" 2 90s but by adding a single 90 you can reduce the sound. Most overflow boxes just dont have the room for it. I have a dual overflow (2 drain lines 1200gph) and I can't use the elbows, not enough room. The cup idea is pretty interesting.