Skimmer question

[Mr31415]

I have a Tunze 9015 Comline in sump skimmer in my 120l QT tank with no LR and no SB. Only 6 chromis are in that tank for the past 2 weeks. I feed them once daily some brine or mysis shrimp. My question is whether it is correct that my skimmate is a light brown colourand VERY watery? I have adjusted the air intake and the water flow but the best I get is a light brownish watery fluid in the collection cup. The cup fills in about 1 week.

[Andrew]

Since you only have six small fish, that sounds pretty normal to me. Tunze skimmers don't skim really dark anyways.