As promissed, here is the response I got from Jason at AquaC.
Questions:
..."The main problems are:
1. Every time food is introduced, foaming stops for approximately 6-7 hours.
2. Every time we cook in the house, foaming stops for approximately 2-3 hours (tank is about 20ft. from the stove).
3. If there is a crowd (that is more than 5 people) in the room, foaming stops and will not resume but after some hours after the room is alone.
4. Even when there is foam, it is extremely difficult to tune. Sometimes it just doesnââ"šÂ¬Ã¢"žÂ¢t make it to the top and into the cup, as foam, and then at times it just overflows with water, not yellowish skimmate, just clear water. If I move anything in the output gate valve, or in the intake ball valve, the results change dramatically. I.e. from no foam to overflown with water."...
his answer:
..."In answer to your questions:
1. It is normal for the skimmer to stop foaming for a period of time after feeding the system - this is due to the oils and chemicals that are released into the water by the food and your hands. These oils affect the surface tension of the water, which prevents foam from forming. You are experiencing a much longer period than normal, however, and this could be due to the foods or additives you are using. Any chance you are using Selcon, Zoe, or a similar vitamin additive that might be very oily? Certain fish foods such as silversides, sardines and other oily substances can also have this effect.
2. It sounds like your skimmer is drawing in some oils from the kitchen - oils and chemicals often become aerosols and drift around your home during cooking, and if the skimmer is near the kitchen, it could be sucking in a lot of these compounds and this is also shutting the foam down. I've only noticed this effect when skimmers are located very close to the kitchen, and the only remedy I can think of would be to place some sort of intake filter over the air valve on your skimmer. Is it possible to run an air line from the skimmer's valve to an outside window for a fresh air source?
3. This is a strange one, and I would suspect that it has to do with the level of CO2 and other hases inside the room when you have a bunch of people in there. I haven't noticed this effect in my systems, but if you've seen it happen on several occasions, I wouldn't doubt that it could happen. The above solution would probably solve that problem.
It sounds to me that there are a bunch of different factors here that are constantly at play, and this is part of the reason why your skimmer has been difficult to tune. Narrowing down some of the problems and finding some solutions will no doubt get things under control...
A couple of other things to check: do you have the auto waste collector top packed with activated carbon? If so, you might try removing some of this or switching to a brand that has a larger granule size. If the air flow through the collector is impeded, it can have a negative effect on the skimmer's foaming and this would be making things harder to control.
Also, your skimmer set-up looks good except that there are two areas of concern: It appears as if the Sen is drawing water by siphoning water off the top of the tank, and I can't help but wonder if that flow into the pump is constant or whether it fluctuates? Do you ever notice that bubbles/air gets sucked into the pump? If the tank water level rises or falls at all, this would be placing varying amounts of pressure on the pump, which would thus influence the flow rate from the pump. Also, if the tank level fluctuates, the output from the skimmer might also be fluctuating since you have the return submerged without a siphon break. The combination of these two factors, along with the above, would certainly explain why the skimmer is so difficult to tune and why foaming is hard to control.
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Jason Kim
President
AquaC, Inc.
9825 Carroll Center Rd., Ste. 400
San Diego, CA 92126
858-689-1121 customer service
858-564-3419 fax
www.proteinskimmer.com
AquaC Spray Injection Skimmers
U.S. Patents #6,156,209 & #6,436,295"
HTH
Omar
