Greasy Film On Top Of Tank

[emilythestrange]

Please help because i was really happy about setting up my 2nd tank and after 2 days of putting my Filter in the tank of clean fresh water (with nothing added just yet), a skin has appeared on top of my water surface

It is an open top tank, i had to change almost all the water when a thicker skin appeard on top of the water surface

Now it has come back but not as bad. i need to know how to stop this urgently

 

[Syphoniera]

Just guessing, but wondering if you're doing a fishless cycle using fish food?
Because the oils and bacteria from that process could, I believe, cause something of the kind.

 

[emilythestrange]

Just guessing, but wondering if you're doing a fishless cycle using fish food?
Because the oils and bacteria from that process could, I believe, cause something of the kind.

No im using Pure ammonia

 

[nosoup4you]

You need to aim your filter outlet more toward the top of the water. This should eliminate the film.

 

[grasshopper_green]

You need to aim your filter outlet more toward the top of the water. This should eliminate the film.

agreed. increased surface agitation may clear up your problem.


I've also heard of using paper towels to soak up a greasy film on the water surface.

 

[petertr]

Happens a lot. Wouldn't worry about it

 

[backtotropical]

I agree with the above that its nothing to worry about and will be solved with extra surface agitation or paper towels.

However, it is my understanding that it is usually caused by overfeeding or the feeding of certain oily protein rich foods. Why it would appear in a tank which has no fish or food is a mystery.

Maybe some kind of air-bourne pollutant?

BTT

 

[drobbyb]

It could be some kind of contaminate that was unknowlingly introduced to the tank on your skin. It could come from many things, but the importance here is that it's probably harmless.

 

[Madhousedavy]

i had this in my breeding trap and breeding net i found its because the water is nt moving on top as i found the rest of the tank was fine.
i think its like the scum you find on top water thats been sitting there for a while its easily fixed by, like they say, the filter head facing the surface of the water and/or air bubbles making a little movement

hope it helps

 

[Tacklebury]

Yeap, lack or surface movement.

I have it on my 28 ltr, its not a problem but looks a bit worrying!

 

[rhostog]

I also got this film when fishless cycling my small tank with ammonia. I did have plants and substrate, so blamed them, but it could be the water or something from the algae etc. I don't get it in the big tank but there's a lot more surface agitation; also the lighting in the small tank makes more reflections on the water so it's more noticeable.

I turned off the filter for a water change, let it settle for a few minutes, then used a clean glass to skim it off, and that cleared it really well. Now there are fish and shrimps in the tank, it comes back occasionally, and I need to do this about once a fortnight, but just for cosmetic reasons - it doesn't seem to be harmful.

 

[saz326]

there is no need to do an entire/100% water change. You can use a piece of hose to create a siphon, and simply allow the siphon to suck the surface water off. This is how I remove surface bits of plant when doing doing a partial water change. (allow about 10% water to be removed)

 

[Tacklebury]

Having only left my lights on for aroun d8 hrs over the last 48 (night shift) the scum has gone?