Tunze 9410 skimmer issue

[glang]

I have had the Tunze 9410 skimmer running since May of this year. I know it takes a while to break in, but mine continues to overflow the collection cup unless I completely restrict airflow. It is also terribly loud because of the excess water tumbling.

I do have the water level at the suggested height.

Any suggestions?

 

[Craig Borowski]

Please check how many rows of pins are on your needlewheel. It should have two rows of pins. (We've had a couple of instances where the 9410 has shipped with the European 50Hz needlewheel which has 2.5 rows of pins.) Let me know what you find and we'll take it from there.

 

[rvitko]

Only to answer the question regarding water level, the ideal is around 6-7", the higher the water level, the higher the flow of the pump as it doesn't have the resistance of the water column in the skimmer, if the water level is very high that is another possible cause.

As Craig mentioned, we occasionally see a 9410 with the 50Hz needle wheel installed by mistake, this needlewheel will have 2.5 rows of pins (2 full length and one half height. The 60hz one has only 2 rows of pins.

 

[glang]

Thanks for the advice. I checked the needle wheel and it correctly has 2 rows of pins. Therefore, I lifted the skimmer up about an inch to lower the water level and will see if that solves my issue. So far, it is running better.

Thanks

 

[mecheng]

Same issue

Same issue

Sorry to revive an old post. But, I also have a 9410 that keeps overflowing bubbles uncontrollably. I have the skimmer sitting on a stand which puts the water level at 6 inches. I have tried the blue knob fully closed, fully opened, and in between. Any way I have it the bubbles come way over the top and fill up the cup. Any suggestions? I already checked the needles and I have the two rows like I'm supposed to.

 

[mecheng]

Also the pump on this thing is deafening. It is so loud I had to turn it off this morning as it was waking my infant. It is much louder than my MAG drive 18. Unit is new purchased from aquarium specialty in July and just started up this week. Could the impeller be defective?

 

[rvitko]

If the pump is loud the most likely culprit is that the bushing at the bottom of the impeller well is not seated in its socket, it should not be loose on the shaft but pressed into a seat at the bottom of the well. It is also possible the shaft is broken, please check this as either can occur in shipping. The noise may also be a result of water being drawn into the air intake by the anti overfoaming feature.

It is not unusual for a newly installed skimmer to foam over, start it with air fully open, make sure the pipe is pressed in all the way in the skimmer base and that the basket is not above the top of the pipe. Close the air as needed but not more than 50%. If any additives which would act as a surfactant have been used, this behavior will not subside until the additive is discontinued for 2 weeks. Such additives include dechlorinator, stress coat, vitamin and amino supplements and most medications/algae killers.

 

[mecheng]

Thanks Roger. Before I got your post (early this morning) I closed the blue clamp almost all the way just to see how it reacted. By doing so, this afternoon when I came home for lunch the skimmer pump has quieted down almost completely and produced a half cup of dark white skimmate. Is this OK to do?

 

[rvitko]

Yes, but you may want to slowly back off the air screw, 1/4- 1/2 turn per day, the less air, the more water goes through, the best way to look at it is the pump does about 450gph and you are just setting the ratio of air to water, it isn't quite that linear due to the density differences but very close. When the water flow is really high with the air closed you can get more splash and water noise and erratic behavior. Dark white skimmate would generally indicate some dust or surfactant present which will also cause this kind of overreaction.

 

[mecheng]

Great. Thanks again for your insight. I will give it a week and follow your directions. I'll update the post to let you know how it goes.

 

[mecheng]

Roger
The skimmer has stopped bubbling over and I have been backing off the screw a half turn a day as you suggested. However, the pump is still the noisiest pump I have on my system. It is a loud surging sound that gets worse when I open up the air control knob. It is pretty much silent with the knob closed. But the surging gets louder and more frequent as the knob is opened. Skimmer is new.

 

[mecheng]

Disassembled the impeller again and found that the innermost bearing was loose on the shaft. I pulled it off and pushed it back into the pump, reinstalled the impeller and started back up. Silent! Also the bubbles dropped inside the skimmer so I can now open up the airline more. Seems the loose bearing was causing erratic impeller movement and excessive bubbles inside the chamber. Problem solved I hope.

 

[rvitko]

Keep me posted, I had wondered about that. It is not uncommon for that bearing to come loose in transit.