Top of water film

[Reefer wanna be]

So everything is running good numbers are ok an i have like a oil film of some sort on top of my water any ideas

 

[2_zoa]

Do you have an overflow? Or is this just a box of water?

If you do have an overflow, how much does the water drop into the overflow? Ie.....1/8" or up to 1" and beyond.....

 

[Anemone]

This is very common. An overflow will take care of this. If you don't have any surface overflow, then a strong surface agitation will be required to break this surface film - this film can inhibit gas exchange.

FWIW,
Kevin

 

[mcgyvr]

Yep.. protein slick.. Very common on tanks without sumps or sufficient surface agitation. Point a powerhead towards the surface of the water to create some movement there to hopefully knock it down..