Evolution Aqua skimmer pipework problem

[thesorcerous]

Hi all,

I have a 100 litre tank with an Eheim Pro 4 250 filter. I have recently installed the 16 mm glass lily pipes form Evolution Aqua. The inlet is the surface skimmer inlet. The problem is if i have the filter on full power, the inlet skimmer part draws in a lot of air into the filter. This air is not clearing in the filter, probably because it's not designed to clear so much air. I have turned the restriction lever on the filter down to half ( advertised rate is 950.00 l/hr on full power). But the problem has persisted. It got so bad earlier this week that the filter stopped! This doesn't seem to happen in other aquariums i have seen with this inlet, like in Aquarium Gardens, where the surface of the water inside the skimmer is similar to the surface water of the aquarium. I have attached a photo of the inlet top to show what I mean.

Any help is much appreciated.

Thanks,
Rob

 

[Geoffrey Rea]

Hey @thesorcerous

Have you tried putting more air under the skim part, like with a dosing syringe to make it more buoyant?

 

[thesorcerous]

Ah, no, maybe that was it! I have just adjusted it now and it seems to be working much better, and on full power.

Thanks for the tip
Rob

 

[Deano3]

My local aquascaping store had a trick and put a rubber washer around the tube on the skimmer part so stays up in the air as i think a few filters cause this problem with them.

Dean

Sent from my SM-G970F using Tapatalk

 

[thesorcerous]

Thanks. It has continued to be a problem. The filter ended up about half-filled with gas, which it periodically expelled, but not faster than the rate it accumulated it. I have ended up putting the original Eheim inlet pipe on the filter again, hopefully as a temporary measure until I have time to investigate and experiment further. I had wondered whether some of the gas might have been CO2, but it's worked fine since I have changed the inlets over, so I guess if there is any CO2, it's negligible.

Thanks again for the advice.

Rob

 

[Sergey]

I had a similar problem with AquaRebel skimmer. My understanding is that the suction from the floating part is too high and the surface part can't catch up filling the water through tiny slits. What I did and it eventually worked is that instead of adding air underneath the floating part, I ended up removing air, using a syringe with a bent needle. Once a bit of air is removed, the floating part sits lower in the water, and more water is coming through the slits.

Also, note that for a squeaky new skimmer, the flow through slits is restricted because of water surface tension, as the slits are pretty tight. After a couple of days, a microbial biofilm is developed on the edges, reducing the tension, and water starts flowing more easily.