Oily film on water surface.

[alanando]

Can anyone tell me what the cause is of an oily looking film on the water surface of my mbuna tank?It seems to have appeared from nowhere but does not seem to be bothering the fish.

 

[Moe]

An oily film can be caused by some types of blood worms or other stuff you may have fed your fish. You can lay a sheet of newspaper over the top of the tank to soak up the film.

 

[Gunnie]

I had that problem on a 10 gal. community tank at work. Once I got tired of the paper towel routine everyday, I decided to try a sponge filter because I had one available. All you really need is an airstone. The agitation the bubbles cause on the surface churn up the oily film and it either stays separated enough that a film can't form, or it gets sucked up by the filter.