what is this on the surface of my tank?
 

hey guys,
what the hell keeps appearing on the surface of my tank? its like slimy and it forms a film or almost a skin and it keeps coming back everytime i clean it off. im trying to post pics but it wont let me. its like these little black or dark brown pieces on the top of the tank. there are some pieces stuck to my live rock too. sometimes when i put food in the tank they dont go to the fish because that film is on top of the water.

is the film similar to an "oil slick" if so aim a power head up towards the surface in order to get some surface agitation going

slick
 

probably from feeding silver sides or missis shrimp

That used to happen to me too. If you don't have an overflow then a protein sheen can build up. I bought a surface skimmer attachment for my HOB skimmer and that worked. But I also found that if I emptyed my skimmer cup and cleaned it before it overflowed then I didn't notice it as much

no its not like an oil slick, its literally these little black peices or blobs that are stufk together by an oily filmy sticky substance. it looks like webs in the water. i heard corals shed could that be it?
and even blowing it around with a power head doesnt stop it from happening. i need to buy a surface skimmer attachment
thanks

Take a kitchen plate and dipping it slightly allow the skimate to flow into the plate until all the slick is gone. You may have to do this a few times

sounds to me like a combination of needing more skimming and more surface flow.

I would turn up your skimmer (if possible) or get a larger one and aim your powerheads towards the surface of the water