Skimmer not skimming

[ced]

10 days ago, I acquired a 2 inch Tridacna maxima (a clam), and I decided to stop my skimmer for a few hours when pouring the live phytoplankton in the tank.
I stopped doing this after 2 days, as I noticed the skimmer was not skimming. So now the skimmer is running 24/7 again, but it hasn't skimmed for more than a week.
I cleaned it as well as the pump, but it didn't help.
Water params are fine and didn't change. Everybody is doing well (the RBTA, the brain, the spawnfrog, all other corals, the fishes, and of course the clam).

It's a remora urchin in-sump skimmer (tank 40G, sump/refugium 20G).

Any idea?
(don't tell me that the 2inch clam is filtering everything )

 

[jasonkola]

it is possible you may have something stuck in the impeller. when you cleaned it did you check to make sure the impeller was free of any debris?

 

[ced]

Yes, I removed and cleaned the impeller.

In fact, when I say it is not skimming, I mean there's nothing in the collection cup (and I lowered it). I can see the water bubbling inside the skimmer though.

 

[E-A-G-L-E-S]

is the skimmer still producing bubbles in the main body? what about in neck?

 

[jasonkola]

did you check to make sure the air tube did not have salt build up in it or any other obstruction. other than that you got me. I can understand it not skimming for a couple of days after being cleaned but not a week.

 

[ced]

the skimmer produces bubbles in the main body, but not much in the neck.

there is no air tube, the remora urcin is only connected to the pump.

 

[Jon Evans]

I have a skimmer on a sump/fuge setup. it doesn't skim out anything either. The only time it skims is when I add supplements. The origional ecosystem method was designed to eliminate skimmers. If the water parameters are good, maybe you don't need one.

 

[E-A-G-L-E-S]

If you don't feed much, there may not always be organics to pull.