What is this stuff on the glass of my tank?

I noticed this stuff appeared on the glass on my tank today. Is it eggs? or something that is not good. Sorry for the dirty glass.

 

looks to be snail eggs..

 

I have a slick that looks like oil on top of water in my aquarium. what could it be and where could it have come from since i have soft and hard corals, How to get rid of it? please help.

 

get and overflow box and a sump. the overflow box will skim the surface and will keep in nice and clean.

 

Cerith snail eggs

 

+1 on cerith snail eggs.

They're good, free coral food

 

BP though that there was oil in your aquarium so their drilled your sand bed ?

 

hahaha wow.... thats hilarious

 

That was so wrong.

 

That slick is normal. Basically, if you stick your hands in there, slick will happen. If you look at the water surface from below the water, it looks like a film with suspended dust particles on it, right?

The way you take care of that, is with the use of an overflow box, or some other type of surface skimmer. If your tank is a reef ready tank (ie: it has pre-drilled holes and overflow boxes somewhere where the water goes in from the surface) chances are you'll lose that slick... but that is not all. In order to really get rid of it you need a protein skimmer, to rid of all the bad stuff that pollutes your water and that is more than likely causing that slick.
By bad stuff I mean rotting food, fish or coral poop, etc.

Do you have a protein skimmer?

- Mag.