Skimmer Fluctuation

[ctiq21]

Hi,

I have a protein skimmer that is kind of old that I purchased from my local lfs. I am not sure what brand it is ( I think it is made locally out of Denver), but it is a hang on with bioballs in it. I currently have the skimmer in my sump(not actually hanging on). I have upgraded the pump from a rio to a Maxi-jet and have received better results. But I am still having a problem with keeping the skimmer working correctly. One day the skimmer will pump out some nice dark gunk and then it won't work for a couple of days. I have tried adjusting the venturi valve and other things but then just end up filling the collection cup in a couple of hours. I am in the process of putting together my doser, but I am still waiting on some parts. Would a small change of the water level in my sump cause the skimmer to fluctuate?

Any suggestions?

[Witfull]

water level can be a factor in skimmers...the higher the level the higher your bubble columb will be,,so if it falls to low your skimate wont overflow into the cup but will build up alone the walls of the lift tube.