Knop Protein Skimmer stopped making bubbles?

[Doug Stone]

My KNOP skimmer has worked fine with it's RIO 800 pump. I came in to check the tank Friday morning and the pump on the skimmer was running but no bubbles just a little tiny tornado. I turned it off. Later I put the pump in a bucket to check and with aeration, it was blowing bubbles fine. I had read several
articles detailing catastrophic failures with this pump so I purchased a Maxi-Jet 1200. I had some difficulties getting it in as the intake side is long and I had to squeeze it behind some Live Rock. At any rate, it blows lots of water into the skimmer but no air as a matter of fact, it blows water out the air intake hose. I took it to the LFS to check it out and we tried several different pumps with the same effect. I cleaned the RIO, blew out
all the openings in the skimmer with compressed air, and put the RIO back on. The skimmer is working fine now. Anyone have any ideas? Is there some cleaning operation I should be performing other than emptying and cleaning the cup?
:eek1: Anyone have an idea why the larger pumps wouldn't work?

[fade2black]

Did you get the venturi kit for the maxijet? There is no way it could have blown water out the air line if it was hooked up correctly. The venturi adapter fits into the intake on the MJ and it pulls water and air into the pump. That, in turn, is pumped into the skimmer. As for the Rio, IMO toss it. If you want to use it make sure the little hole that the airline attaches to is clear. Otherwise it will just pull in water.

- Fade

[Doug Stone]

There air intake appears to install on the outflow side of the unit. Are you saying it should be on the intake? I know if you hold the pump partially out of the water, it blows air with water just fine..

[fade2black]

If you put the venturi adapter on the output it will never work. It has to go on the input, it's the only way the pump will pull air into the impeller.

- Fade

[tomatoeclown]

Doug you need the turbo venturi made for all Maxijet pumps to make them true ventury pumps, trust me the same thing was happenig to me till someone else helped me out and told me abou it, go to www.premiumaquatics.com it's under pumps/powerheads under Maxijet powerheads it's $3.95, shipping is steep close to $8.00, pay 1 to 2 more $ and order something else, thats what I did, makes the shipping worth it, cya.