# film on top of tank



## djj123 (Mar 18, 2010)

hi ive got a fluval u3 filter yesterday i changed it to the bottom outlet now today theres a film across the top of the tank also im in the first week of my fishless cycle also does my filter aireate the tank when using the top outlet cheers dave


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## Byron (Mar 7, 2009)

I'll leave it for a member who has or has had a Fluval to answer you on the filter part, but as for the film, not to worry. On every new tank I've set up there has been a film which disappears once things are coming together. As you're doing fishless cycling I'm not sure how long this might be, but with my tanks which are heavily planted with fish from the start (because of the plants) it is only a couple days.

There is a second type of film, a protein scum, that can occur in established tanks if the surface disturbance is nil. It is basically harmless, I tend to see it more in one of my 3 tanks and just syphon the water off from the top at each water changes to get rid of it. If you don't have live plants you can set the filter return to create a gentle movement across the surface and that keeps the protein scum from forming.

Byron.


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## iamntbatman (Jan 3, 2008)

I've heard that people with planted tanks have had success using surface skimmers to deal with protein buildup. It removes the film without disturbing the surface enough to really affect dissolved CO2 levels. 

Something like this: http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=12703


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## Byron (Mar 7, 2009)

iamntbatman said:


> I've heard that people with planted tanks have had success using surface skimmers to deal with protein buildup. It removes the film without disturbing the surface enough to really affect dissolved CO2 levels.
> 
> Something like this: http://www.fosterandsmithaquatics.com/product/prod_display.cfm?pcatid=12703


Yes, those work very well, I had one on each of my three tanks with the Eheim canisters for years. I've removed them now, though, because the small fish kept getting sucked in to the filter. And in the 70g, where the protein scum occurs, I have spawning Chocolate Gourami and Pygmy Sparkling Gourami and the fry hide out in the floating mass of plants and would easily get pulled in. You can fix screen over the openings, I just didn't want to bother.


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## eileen (Feb 24, 2009)

Sometimes food that has a high protein content causes a film on the surface of your tank. I bought a Bio System Power filter & Oxy Surface Skimmer from drsfostersmith. They are on sale now at 25% off. I have one for my 55 gal. and bought 1 for my new 20 gal. tank as I like them so much. The largest size is a 75 gal. for $29.99. The filters from drsfoster smith are on sale also 24 pk. for $12.69. I rotate the filter cartridges because mine uses 4. the old one goes in front and a new pad goes in back. This saves money and I have had no problems doing this.
The skimmer does however suck up fish. I removed my skimmer and just have a reg. filter but this one is still good as I do not have a film over the top of the water. This filter has a control dial to control water flow. I also put a sponge over the intake so baby fish would not get sucked up.


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