film of something on surface

[vromanowski]

I bought a fluval cannister filter about two weeks ago, and since replacing the HOB a film of something has formed on top of the water. any ideas what this is?

 

[corrado33]

Is it green? Or is it a film of dust? Do you have surface agitation? I'm guessing it's just a film of dust.

How often do you do water changes, how much do you change?

 

[vromanowski]

No surface agitation since the HOB is not there anymore, so I know that's why the film has appeared... I just don't know what it is :/
It's not green, it's clear actually.
I do partial water changes either every week or every other week...usually 1/4 change for the former and 1/3 to 1/2 change if it had been 2 weeks!

 

[dkpate]

Is it irridescent?
You need surface agitation to create oxygen in the water for the fish.

 

[corrado33]

Agreed, just angle the outlet from your filter toward the surface.

 

[BigJim]

The film is stuff from the air settling on the water. You'll need to agitate the surface to break the film. This will cause the stuff to sink into the tank and get filtered out. The film reduces the oxygen exchange between the air and water.

 

[vromanowski]

I'm injecting CO2 for my plants though, that's why I bought the fluval, to get rid of surface agitation so the CO2 didn't escape :/

 

[corrado33]

A little surface agitation won't hurt anything. You could always try to use a different CO2 diffusion method...

 

[Dr. Scroggins..]

i went through this about a month ago. i also inject co2 for plants, i bring it in through the smaller sized air stone which goes in to the intake of a power head (does a really nice job of producing very small co2 bubbles). to fix the situation i put an air pump on with two of the smallest air stones (one in each of the back corners). So my air pump and co2 are on opposite timer schedules. the co2 comes on with the lights in the morning and the oxygen shuts off, the oxygen comes on when its dark and the co2 shuts off... so basically when my lights are on, the co2 is on. when my lights are off, my oxygen is on.. no more film. check into a timered power strip (20$), they have day and night (alternating) plugs, makes it so simple. i ended up putting my co2 on 2hrs before my lights come on, that way they have all they need in the water as soon as the lights shine. and my drop checker is always green so i know there is ample co2.

 

[corrado33]

i went through this about a month ago. i also inject co2 for plants, i bring it in through the smaller sized air stone which goes in to the intake of a power head (does a really nice job of producing very small co2 bubbles).... other stuff

That's a great idea. You don't really want a lot of CO2 in at night anyway cause the plants are no longer producing oxygen so your fish will suffocate. And that's no good. I like that idea.