Eheim Surface Skimmer

[bbrown]

I recently set up a 50 gal freshwater tank with an eheim professional series canister filter. This is the first tank that I have used a canister filter on. I have the output directed approx. 2 inches below the water level. There has consistently been a skim on the surface of the water. First, can someone pls explain why this happens.
I have an eheim surface skimmer accessory (which I acquired from another eheim model (2213) which I connected to the filter (this is just an attachment to the input). However, I have no manual on how this is supposed to work. It does not appear to completely remove the skim so I'm thinking maybe it is not adjusted properly. Is anyone using this equipment and can explain how to properly set it up?
I looked on Eheim's website - here's the link to what it looks like http://www.eheim.com/skimmer.htm

[jcarlilesiu]

funny that you should mention this. I have a 56 gallon column that is heavily planted, and recently i have noticed some surface film also. This is usually caused by excess proteins in the water i believe. I have a bit of cloudy water too, however i use a HOT magnum canister.

I know excess film doesn't cause any ill effects to your inhabitant just athestically doesn't look so good. The only recourse i know of is to skim the top of the water with a plain white, paper towel with no fragerances.