9006 foaming habits

[Modaq]

Hi Roger

I suspect my skimmer is underperforming. I have written to you about this model before: http://www.reefcentral.com/forums/showthread.php?p=18180239

Is it normal for this skimmer to be completely knocked back by the first feed of the day? Suspecting that it is underperforming, I have been monitoring it, and note that it only begins to produce any (any) foam four to five hours after the lights have gone off in the display tank, and the foam column will 'collapse' as soon as the fish are fed, an hour or so after lights on.

It is currently open 4.5 turns, and I will experiment by opening it further. For many months, I have been content with only a dribble of skimmate a week. However, now I am confident that there is much to skim in this system (I have an outbreak of brown diatom algae), and yet it seems to only manage a few millilitres of tea-coloured skimmate in the dead of night.

Would you please advise on the above please? I am confident it is fitted together correctly, regarding air line, nozzle etc, having disassembled it many times, in search of a fault. The only other thing I can think of is that the chamber in which it resides has too fast flow. Is this a considerable issue with this skimmer?

Thanks

Yours

Joe

 

[rvitko]

Fatty or oily foods will cause skimming to slow or stop, this is pretty much universal. Many vitamin and amino acid supplements will cause the same. If the flow rate is very high through the sump, the skimming will very likely increase if this is cut back and it will also help with the reaction to food as the food oils will reach the skimmer more slowly and in lower amounts at a time. I would start by cutting the flow through this chamber to 4-5 times the tank volume per hour and increase the turns of the air screw.

 

[Modaq]

Follow up

Follow up

Hi Roger

Just to let you know, after opening the screw all the way up to 6 - 6.25 turns, I finally have a fairly constant foam. Brown diatom algae has disappeared.

Incidentally, flow rate was/is about 4-5 times total volume of the system's water.

Lastly, while performance is now good, the unit is not quite as silent as it was. An intermittent sucking noise can sometimes be heard. I have tried removing the air-screw and cleaning this whole area with a cotton-bud and pure water, which helps a little, but does not eliminate the problem. The skimmer is also fairly entombed among pipes etc, so if you can recommend an in-situ solution to cleaning/silencing, this would be preferable.

Many thanks

All the best

Yours

Joe

 

[rvitko]

This noise would mean water is being sucked into the air intake, usually this happens if the water level is a little high or has a wave and surges up higher, lowering the water level just a little, 1/4-1/2" or about 1cm should help.