Noise normal with 9004DC?

[Helfish]

@rvitko could help me out here

I have had the Tunze 9004DC for few months now, and to me it seems that the noise coming from the skimmer is getting louder. At the beginning it was quieter and now seems to produce this gurgling sound. Can you tell if this is normal or not?

The skimmer is placed inside tank with osmolator to keep the waterline in check. The waterline is 8mm from the the bottom of the front grill. I remember reading advise from you to keep the waterline between 5 - 10mm form the bottom of the grill, is this correct?

It is skimming and there is foam coming, very thick foam. I am also dealing with microbubbles, but this seems to go and come every few days.

I have set the aircontrol to level 4 from the controller, however I am unsure what does translate in %? It is a bit confusing to read, as the knob can be turned all the way to the right.

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[rvitko]

I would be almost sure the air intake is clogged at the impeller cover, this typically becomes an issue after 3-6 months of use. A quick though short term fix is to place the air hose in a shot glass of hot water and let it pull the hot water through, this generally works better as monthly preventive than fixing an already clogged intake, in general the best fix is to break the skimmer down and clean the nipple on the impeller cover that the air hose is attached to.

 

[Helfish]

Thank you for the help. I took it apart and there was some gunk on the air intake at the impeller cover. It much quieter now, though this loud sparkling sound (like listening carbonic drink) is still present.

I must say, this thing is not the easiest to take apart and put back together. I bend one of the fastening clips during the process. Could be easier to disassemble, if you want to forward the feedback to Tunze

 

[rvitko]

It takes practice, what works the best is to start at a top corner and pull and it will basically unzip, until I learned this trick, it was very difficult. Let me know if the noise does not improve, it should be almost silent with the cup on, with it off you definitely hear the bubbling water.