[Delphinus]

To be honest I have the same complaint about my G3x. (I think it's a G3x, if not it's a G3 anyhow). If I get a 1" of skimmate in a week that thing is doing well (I use the term "doing well" with a sarcastic tone).

One thing with mine is it's modified to be recirculating and is fed from the overflows, which I now gather is a "no longer recommended approach". Although I don't really think this is the problem with mine.

What I have noticed is that the venturi is *incredibly* prone to the slightest of blockages. What I've had to do is, on a weekly basis, take a nail (or other long thin tubular item, like a drill bit that you don't care if it gets SW on it), and scrape out that air inlet in the venturi. If I don't do this, the foam production will drop off very quickly after a few days. It seems that air inlet is really good at gathering a slime layer that impacts the airflow through it.

Some people drill out their venturi's to make the hole larger, and in fact some people remove the air inlet altogether and tap out the hole for a hose barb that allows more air in.

As soon as I get my airflow meter that I ordered, I'm going to modify this unit into a meshwheel (basically remove the needles off the needlewheel impeller and replace with two layers of enkamat). People are raving about this kind of modification on their needlewheel skimmers (any needlewheel) so it should be a positive move. I'm thinking I might also be trying the tapped hose barb mod on the venturi. I'll let you know how it works out.