Increasing flow of a hang-on overflow box?

[j_chicago]

Thanks, Matt. I thought the only thing that controlled the flow rate would be the distance differential.

That's why I love this forum so much, there's so much garbage and misinformation out there.

 

[j_chicago]

The only other thing I could say would be to lower the overflow box on the rim of the tank as much as possible - most boxes have little plastic screws to adjust the height of the box, and therefore the water level in the tank. If you get the box as low as possible, this might allow a larger pressure differential from the front to the back to bump up your flow a little.

Sorry, you mean the skimmer box inside the tank, that has a screw, but wouldn't that lower the water level in the tank and lower the flow rate?

 

[Sploke]

Maybe you can post a picture of your overflow box. Mine are all one unit, so the whole thing would lower at once. So, if you increase the height the water can get over the skimmer box, it would increase the height difference between the tank water level (before it starts overflowing the tank) and the back compartment of the skimmer.

 

[j_chicago]

I took some pics now as I am working on it and I'll get them uploaded later. Basically there is a screw to raise and lower the box inside the tank. The outside box is stationary. So I was able to get a little more flow and I'm going to drill my siphon breaks and leave it till next week and pick up another U-tube. Now I'm worried that my baffles are too high and think I need to cut them down to allow more room in the sump incase of a power outage.

 

[j_chicago]

Update: added a third tube today and now have the pump's valve all the way open, and getting a lot better flow through the sump.