Any 60 cube owners out there? Plumbing/Overflow question!

[kelvindodd]

So, I've searched the forums and even went to my LFS for advice (bad move) on a plumbing question. No dice.

Deal is this; currently have a Marineland/Aqueon 60 cube with factory overflow. I have a 90 turndown directly behind the tank leading to my sump (with another 90 down). It was suggested by the LFS to purchase a Sicce 3 for my return pump. Problem is, I have to turn the pump adjustment all the way down to keep the overflow from backing up, then sucking water like a vortex. Turned all the way down, the flow is extremely minimal, but quiet.

After getting frustrated at my lack of flow through my 1" overflow, I asked how I could increase flow without adding noise. I was told (again by the LFS) that overflow should handle way more than was it currently was. He said to drill a second vent (see pic) and add another (larger) breather tube. After that had no effect, he suggested I drill holes in the side of my elbow. That has had no effect either, so I'm stuck with the two options of quiet (almost no flow) to having the sucking/slurping noise if I turn the pump up at all.

Is this a limitation of the type of overflow? Are there any workarounds or will I have to disassemble and replace entirely to get any more flow out of it?

[JeF4y]

It's a huge balance of getting the right angles of the hoses down, and then finding just the right drain into the sump...

I ended up making a reverse durso in the sump (google it) and it was STILL flushing. After about a month, enough slime built up on the new hoses that it stopped making noise. Now it's virtually silent, but it took a lot of near sleepless nights and frustration to make it that way.

Additionally, I played around a LOT with the diameter of the pipes used for the durso at the sump end, and the depth of the drain into the sump, etc. All of it plays a part...