Problems w/ Alpha Kone 250 Skimmer

[njreefermadness]

I have been having problems lately with my Royal Exclusiv Alpha Kone 250 skimmer. The pump is running fine, but when I attach the air hose to it, it slows down and pulls very little air. If I submerge the tubing slightly and it starts to "slurp" water with the air, the skimmer pulls air like crazy and foams almost like normal. If I pull of the air hose completely, you can feel it pulling at the pump inlet like normal.

I cleaned the impeller, which had a lot of crud and bits of worm tubes and limpets in it. I thought the impeller cleaning would do the trick, but no go.

If I put a slightly oversized air tube on the inlet, so the pump pulls some water with the air, it works almost like normal. It makes a tremendous racket though, and this is not how this baby should be working.

I really love this skimmer, but I can't understand what is wrong with it, as it has been acting up a bit lately. The skimmer is about 2 - 3 years old.

Any thoughts on what could be the problem would be appreciated.

Thanks.

Herb

[AquariumSpecialty]

The only thing we can come up with is that the sponge in the silencer may be dirty or wet or both. Remove the sponge and see if it needs to be cleaned. Also, make sure the air tubing is free and clear of debris. If this doesn't fix the problem then give us a call. We got your voice mail message over the holiday weekend also.

[njreefermadness]

All of the above has been done. Even running w/ just the silicone tubing w/o the silencer has the same problem.

I actually put a hole in the tubing below the waterline, and inserted a small piece of plastic tubing to draw some water w/ the air, and this seems to get the skimmer working like it used to. W/O the water draw, the pump slows down and barely pulls any air.

Very strange.

Herb

[AquariumSpecialty]

I will share your comments with some other folks to see if they have any other ideas. This one's a mystery to me at this point.