Film on the surface

[krowland]

I've got this film on the surface of my Oscar tank. I can't figure out where it's coming from. I do regular weekly water changes, the parameters are all fine. They're not overfed so I'm at a loss as to explain the film. Any ideas on its source as well as a remedy?

[slipknottin]

more surface disruption will get rid of it.

[JamisonBWolsh]

check your nitrates? are they high?

[TwoTankAmin]

I have the same problem. Mine is due to my being a smoker. However, it can also result from a forced air heating system. As pointed out more surface aggitation should help. If you are a smoker you may want to try one of those Ionic Breeze air cleaners from the Sharper image.

[krowland]

Nope, not a smoker. I have 2 2028 Pro II's as filters on my 125 gallon with a spray bar on either end of the tank. Perhaps an air pump with an airstone? The filters are running full steam.

As for nitrates, they are routinely in the 40ppm range despite weekly 20% water changes.

[slipknottin]

try moving your spraybars closer to the surface to disrupt more water.

eheim also sells "surface extractors" which fit on the input side of your filter. these will take in water from the surface and below the surface at the same time.

[krowland]

I'll look into the surface extractors as well as move the spray bars. I have them pointing up towards the surface right now from about 2 inches below the surface and I can see a "dead" spot in the center of the water surface with little agitation. Thanks for the input.

[JamisonBWolsh]

here is what a few people from the usenet says:

1.) The oily substance at the surface is likely the result of oils present in
commerical fish foods. Typically not a problem as long as you maintain your water
changes. You probably are overfeeding....everybody does :) Just watch the
nitrate level, 20 ppm is a good number for FW, but can go a little higher without
stress to the fish. Nitrates are a relative indication of overfeeding and
cleanliness of the tank.

2.)Bateria that has died forms a oily skin on the surface of the water, this
are the bacterial 'bodys'.

3.)A protein surface film is said to possibly reduce the oxygenization transfer
but is otherwise harmless.
4.)I found that some foods that are particularly oily do this in my tank. I
feed my breeding guppies specialised guppy foods and two of them have high
oil content. what the guppies dont eat leaches the oil into the water and
you get a slight film on top. As long as your not overfeeding it shouldnt
be a problem and does clear. you might want to consider another food if you
have labarinthine fish in though, like gouramis and betta's. The film can
cling to them when they come up to breath and cause problems later on if
they get a buildup on them.

5.) It's a protein / oil film most often seen in planted tanks. The common methods
of getting rid of it are surface agitation, a surface extractor, or just
floating a paper towel or newspaper on top of the water for a moment. for
such a small tank, I'd just go with a paper towel every once in a while.

So there are 5 different response. I never had this problem, so dont know what to tell you. It doesnt cause a problem though, as the other poeple have said.

[w9nwr]

:D
Thanks to TwoTankamin the surface film problem for me is solved.
I am setting up a 50 gal FW, just about a week old. After a couple of days noticed a slick on the water surface, collecting it by skimming it off (into a glass) produced white filament type products. I searched for days trying to find the reason. Lots of good advice but only on tanks that we pretty much cycled and running.
TwoTankAmin mentioned forced air ...tank is built into a middle wall of a rec room in the basement in the area of the furnace but not in direct line with the vent. I built a cover from plexiglass and let that sit overnight. With the furnace going yesterday and last night (North Wisconsin, it runs a bit!) this mornings inspection showed no "slick" on the water. Looks like problem solved!!
Now I wonder how much light that new cover and the subsequent condensation on it is going to block? May have to look into a more powerful system. running two 48" full spectrum at 40W each. (T12). Tank is about 20" deep.

Thanks TwoTank for your post.

Now I wonder what products the forced air is putting into the air to produce that slick?
Maybe this will help someone else also.

Chuck