Shiny Film On Water Surface?

[dorecs]

Hi,
 
On the surface of the water in the tank there is a very thin film-like coating which reflects light a bit like bubble,
If I touch it it breaks up a bit and then reforms,
 
What is this and what can I do about it?
 
Thanks

 

[Leesey]

As far as I'm aware its skim mate. Caused by dissolved solids in the water.
It can be removed by pushing a cup bottom down into the water and effectively skimming it off the top of it hence getting it off and improving gas exchange with the water.

 

[WILDER]

It can be caused by greasy foods.
Just float kitchen paper on top of water surface to remove it.

 

[sawickib]

i get this film randomly sometimes as well in my 75 and 55 gallon tanks, i feed frozen bloodworms, so would it be the dissolved minerals? 

 

[WILDER]

i get this film randomly sometimes as well in my 75 and 55 gallon tanks, i feed frozen bloodworms, so would it be the dissolved minerals? 
 
Bloodworms can cause an oily film on top of the tank water Just remove it by floating some kitchen paper to soak it up.