Has Someone Sneezed In To My Tank?

[themissingelf]

Excuse the rather blunt description, however, fished out small patches of what looked like very clear snot from the water surface of my tank tonight. I would not have seen them had it not been for the bubbles from the CO2 diffuser gather on the underside. Anyone know what these patches may be?

Possible influencing factors:
- Water change last night (although never had the problem before).
- Co2 looks like it's about to run out (cylinder pressure dropped).

Can't think of anything else I've done differently.

 

[mikster]

Does your filter move the surface of the water alot? if not then it may be a build up of algae and organic compounds.

 

[themissingelf]

Only a very gentle movement on the surface, so perhaps you're right. Just never seen anything like it before.

Cheers