I've got a setup problem....

[Theo A]

75 AGA tank, C2C overflow

DART for CLS, OR 3500 for return pump. 20l sump, MRc1 skimmer, yada yada...

Problem is with the CLS. It was suggested to me to use one of my 2 1.5" bulkheads in the overflow to feed the dart for the CLS.

My origional plan was to have 4 1" bulkheads for the CLS return, and 2 1.5" bulkheads for the feed. I was going to basically use a piece of PVC cut lengthwise in half, with slits in it, spanning the tank lengthwise for the CLS intake. the 4 1" bulkheads were going to be the outlets.

The way it was suggested (and the way I tried setting it up) is to use both the 1.5" and the 1" (I only drilled 2 1" holes so far) for the return, and use the other 1.5" bulkhead in the overflow as the feed. Problem is, it's sucking air like a mother NOW, and I don't even have the OR return pump hooked up/on. After the tank is actually draining into the sump, the water level in the overflow box is going to be even lower



How can I keep this thing from sucking bubbles? I guess I could turn down the output a bunch to limit the intake, but thats really limiting the pump. Should I swap out the dart for something else?

Please ignore the return setup, I havn't (obviously) finished it yet.


Pics attached. DART feed is on the right from the back of tank shot.

[Red Firefish]

It sounds like there's a finite amount of water moving into your overflow as it is right now, and without drilling an equalizer hole to allow more flow into the overflow area, you'll likely continue having bubbles. You could turn down the outputs on your closed loop or sump return, or downsize your pump(s) to limit the overall draw of these pumps. I think this is what you're asking.

Either way, flow eductors might help recover that lost water movement without drastically re-engineering the system. Good luck!

[datablitz]

try turning the train that goes to the the sump so the 90 faces upwards. that should let the water level in the overflow stay higher and avoid sucking? just a guess