overflow not skimming surface?

[ultra spikey]

Ive been running an Amiracle HOB overflow for a couple of days now. Ive noticed a build up of "gunk" at the surface of the water. Then I looked closely at the overflow and it didnt really look like it was skimming the surface of the water. Is there anything I can do to improve this???

 

[Hop]

Increase the surface agitation... What are you running in the way of powerheads and/or closed loops?

 

[sjm817]

If you try to put too much flow though the overflow, it wont surface skim. The water level in the inside of the skimmer box must be below the bottom of the teeth. The water has to "fall" into the skimmer box. If the water level of the outside and inside are the same, it wont surface skim. This is true of any overflow.

 

[bgiles11]

What type of overflow? Is it a pre drilled. Or is it a a wet dry with a hot box? I had the same problem with my corner overflow. I have two returns and what they were doing was pushing all the surface organics into one corner. All I did was buy another powerhead to agitate the surface a little, and problem solved.

 

[manderx]

fan/pump placement can also keep it from skimming.

 

[lvreefer]

It sounds like you need to raise the overflow box higher above the surface on the water. This will cause the water level to rise and force a surface skim. If this works for a short period of time then stops, you could be forcing too much flow through the box. To test this, slow down the flow and see if it starts to pull from the surface rather then just underneath it.

 

[ultra spikey]

i have 2 powerheads pointing slightly at the surface already. I did set the overflow box as low as it can go, so that the water level in the display wouldnt be so high(i wanted that extra "overflow" room). I guess I can try raising that up a bit. Also, I dont think im putting too much flow through it. I'm only running a Mag7 going through a SCWD, so im guessing about 300gph.

 

[Aquarist007]

setting up the power heads on a variable timer for one min intervals will help--that way you are getting a more turbulant flow rather then a laminant flow which is smoother and will allow less of the surface to be skimmed

 

[sjm817]

<a href=showthread.php?s=&postid=9999072#post9999072 target=_blank>Originally posted</a> by ultra spikey
i have 2 powerheads pointing slightly at the surface already. I did set the overflow box as low as it can go, so that the water level in the display wouldnt be so high(i wanted that extra "overflow" room). I guess I can try raising that up a bit. Also, I dont think im putting too much flow through it. I'm only running a Mag7 going through a SCWD, so im guessing about 300gph.

Is the inner water level below the bottom of the teeth? If its not, it wont surface skim.

 

[ultra spikey]

well...I raised it a little and its skimming the surface perfectly. The only thing is, now that the box is higher, its creating small bubbles when the water goes through the teeth and down into the box. Most of the bubbles dont make it to the u-tube, and the ones that do go right through it.

 

[sjm817]

If the water drops into the skimmer box, it will make a few bubbles. No big deal. But as before, if the water does not "fall" into the box, it wont surface skim. The slick just stays on the surface and the water goes underneath it.

 

[bayreef]

overflow

overflow

i agree water has to fall. raise box (make sure pump is not too strong