No Bubbles in Protein Skimmer

[Davis102613]

My Coralife 65 gallon protein skimmer is not producing all bubbles.

What looks like the air intake for the pump is filled with water, when I blow into it, it makes bubbles properly, but I can't get the water out.

Anyone have any tips?

 

[stempy]

Just make sure the air line is outside the water and that there is no blockage in the silencer, and that the end that connects to the pump is on securely. Other than that it should draw air in. I'm also just gonna assume this is on a salt tank.

 

[duanes]

I find the air intake end of airline needs to be above/higher than the surface of the water in the skimmer contact chamber.
The pump also needs to be strong enough to overcome head pressure. And you may need to adjust (fool around with) the water pressure valve, with mine, the valve needs to be throttled back a bit.
I use my fractionators on fresh water, and they work wonderfully, below a video of one working on my koi pond.

Note the height of the air suction tube (M) on this DIY plan, just a tad higher than the top of the reaction chamber (Q)

 

[stempy]

Those are different than the coralife protein skimmer he's using.

 

[duanes]

Although my DIY skimmers are different, the concept is similar, Bernoulli's equation. Air (gas) is drawn into the water (liquid) thru a venturi valve. If the pump flow is not strong enough, the venturi won't draw air, if the head pressure of water against air is too much, the venturi won't draw air.
I make my own skimmers, because I have found unless conditions are absolutely perfect, commercial protein skimmers wimp out. I also believe this is why people think protein skimming doesn't work on fresh water, the pumps provided are always too wimpy. I always oversize the pump, and in that way have enough head room to throttle back the pump, but increase pressure if crud or anything else starts to impede flow (pressure).
below a venturi, on a counter current skimmer (similar to the OPs)

 

[Davis102613]

Thanks for all the replies guys!