slimey/ oily water

[dea]

hey my 29 gal reef has been up for months now and my water still has a slime feel to it and wheres theres no water on the glass theirs oils on the glass?

what is this? when i take my hands out of the water, it feels liek i have soap or oil on them they are slippery!

[Gonefishing]

Are you skimming the water surface? I assume its a saltwater tank, if you dont remove the surface scum with some type of skimmer it will build up & I would think it could be oily. Without more info on your sustem its hard to give a answer, maybe someone else has an idea!!!