Green Film On Top Of Water

[poohbear]

Hiya,
not been on this forum for a few years but for the past couple months I have had a problem with my 190l corner tank.
I do water changes once a month and check the nitrides, nitrates etc before I do that.
The past few months I have had a green film on top of the water, not much algae in the water just this film on the top.
I have tried a blackout and using paper towels to skim the green film off but it keeps coming back.
Does anyone have any ideas
Thanks

 

[Fluval-1200]

Believe its called bio film, you need surface agitation.

 

[poohbear]

I have surface agitation with the outlet for the filter being slightly higher than the water

 

[star4]

Have you checked your tank lid/condensation tray/glass sliders for any algae build up that could be dripping into the tank with condensation? I have had that happen before.

 

[sawickib]

first off water changes should be done weekly, and clean filter in aquarium water monthly. The green film is mostly likely due to stag net water, if you get a stronger filter or strong air pump should get rid of that.
25% change weekly* whats your paramaters, filters, and stock?

 

[poohbear]

I have had this tank for 7 years now and always tested and done water changes once a month.
The filter is the same filter that came with the tank. I test using a liquid test kit and all the parameters are fine. There is surface agitation with the water from the outflow filter pipe.
I am using paper towels to skim up the film but the next again day it is as bad as ever.
I have kept tanks for 15 years now and this is the first major problem I have had

 

[sawickib]

ok so I feel like I got you mad because you want to tell me how long youve been keeping fish, so you can just ignore my advice then.

 

[poohbear]

No I didn't get mad, I just pointed out I have done maintenance of my tank the same since I first started keeping fish and that there is surface agitation.
I am open to all suggestions as I use papertowels to get rid of it then the next day it is as bad as ever

 

[Antoniakr]

You might need to get a stronger Filter, if you've had it for that long surely it will be a lot weaker, My 8 year old filter still works but its not as powerful anymore. Your filter might not be powerful enough for your tank size. maybe do a full clean of your tank and see how it goes 

 

[poohbear]

Thanks got my nephew coming tomorrow to help me do a full clean so will see how we go from there. Also ordered new bulbs cause I don't think my husband got me aquatic ones when we replaced them