Tunze DOC 9004 anti-overfoaming feature?

[economos]

hi,
Installed the 9004 yesterday and the written instructions suggest running the skimmer with air intake fully open to start. I did that and the cup quickly filled with clear tank water twice. I tightened the adjustment screw all the way down and then backed off about a turn and a half and am now getting about 2-3 tablespoons daily of dark green skim.

Do I now need to open the air intake close to full and trust the auto-adjustment to kick in. Will the anti-overfoaming feature find the balance point without my interference?

 

[rvitko]

The anti overfoaming only prevents a major cup overflow, it does not auto adjust for skimmate color and density. I would keep it where it is and slowly open 1/8 turn per day to try to find the sweet spot of maximum performance without going to wet. It will take more air as it breaks in.

 

[economos]

Hi Roger,
Thanks, that makes sense.
In your experience will the micro bubbles stop after a couple of weeks, or should I purchase the foam pad to insert in the bottom? I'd rather leave it open grid without the pad if there's a good chance the bubbles will reduce soon.

 

[rvitko]

It should settle down within a few days, I might double check that the pump is properly clipped in, they can come loose in shipping. Also be careful with additives, many vitamins, stress coats, amino acid supplements, slime algae killers, etc change the surface tension and make this problem much worse.

 

[economos]

Thanks Roger. I found that the main source of the micro bubbles is a constant leak along the seam on one side where the front section attaches to the body of the skimmer.
Is that an indication it is not assembled properly,or something else? The gap is no larger than the one on the other side that isn't leaking.

I took it apart before installing because I had to reseat the air intake plate that sits over the impeller. It did come loose in shipping. I didn't notice any issues with with the pump being loose though.

 

[rvitko]

I have seen this before and the culprit was a strong source of flow near or directed at the skimmer which basically created suction on the far side of the skimmer as the flow went by and drew bubbles out of the body. Check for any flow aimed at or that is under the skimmer.