Film on tank

[MarkW19]

Over the past week, I've had quite a thick film developing over my 10G nano. I have a PH pointed at the surface, but even that doesn't break it up.

If I scoop it away, it breaks it up a bit, but then 30mins-1hour later it's back again. Whenever I put anything into the tank, it comes back covered in brown sort of algae, so I guess it's algae related.

I don't have a skimmer.

Can anyone help?

 

[lando]

I get this from time to time on my 12gal nanocube. It ussually appears when the suction cups on my powerhead come loose and the current no longer aggitates the water surface. Just use a a very fine "brine shrimp" net to scoop it up. More surface aggitation may be needed.

 

[MarkW19]

Well, I've had a slight film from day one really, but before it was just very minor. This last week it's got a lot worse, and it's even more annoying when it comes back so soon after it's been scooped (less than an hour!). The same powerhead has been pointing at the surface since I started my tank 2 months ago, so I've no idea why it's started doing this now?

I already have a low pH, so this film probably hindering gas exchange even more, can't be helping

It has coincided with a bit of a red/green algae bloom.

Maybe a couple of PWC's will sort it out? I'll temporarily try another PH pointing from the opposite end, if needs be.

 

[lando]

Certainly doing a PWC will help. It is most likely DOC in the water.

 

[MarkW19]

I'm doing a 30% PWC tomorrow, so I'll see how it goes after that. The only thing I've done differently recently is adding less than the recommended amount of DT's just ONCE a week, but that won't be anything to do with it will it?

I guess the DOC's have gone up recently with the addition of all my new corals? Perhaps it just needs a couple of PWCs to sort itself out/readjust?

I wonder why there's brown algae on the water surface though?