scum?

[heather821]

I have had my saltwater tank up and running for about a year now. Recently, the tank has gotten a brownish scum at the top of the water. The protein skimmer is running good. Any suggestions as to what this could be?
Thank you.
Heather

 

[bigarn]

Have you cleaned it recently? How's your Nitrate level? How many occupants are there and how big is the tank?
When I said cleaned it, I mean the skimmer.

 

[heather821]

It is a 55 gallon tank. The skimmer was cleaned last week. The nitrate is high but has been higher and we have not had the scum before. I am in the process of many water changes and have brought down the nitrate level a lot.

 

[tizzo]

What kind of skimmer is it? And does it still get as "gooky" as it always did?

 

[bigarn]

It's probably excess nutrients....Cut back on feeding and do 10% weekly water changes until it clears up.
If you have a PH aim it towards the surface.

 

[heather821]

It is a prism skimmer and yes, it still gets gooky.

 

[tizzo]

Oh, I was curious because sometimes the airline will get clogged with salt creep and make the skimmer less efficient.
Any LR or LS additions lately? :notsure:

 

[dskidmore]

Is the skimmer fed by an overflow box or an underwater intake?

 

[sergeant]

The tank has been runing for a year, isnt that the time to change the lights?

 

[nm reef]

Scum will tend to collect on the surface if there is no surface overflow or if there is a lack of surface agitation. I'd suggest using powerheads to break the surface...this will keep the "scum" suspended and allow your skimmer to remove it. Any sort of surface overflow will also remove the 'scum" but if you don't have that option available then simply breaking the surface should work fine.