Pool light sludge...grease or algae?

[gamble007]

Hey all,

Total noob question, but I'm currently replacing my pool light and when I separate the lens from the casing, I quickly realized that the casing was full of a greenish/brown sludge. It looks like grease to me, but I can't for the life of me figure out why anyone would put a large amount of grease inside a pool light enclosure. My only other thought is that it might be some form of algae, but I've never seen it so concentrated like this. I've attached some pictures so you can see what I'm dealing with. Thoughts?

 

[YippeeSkippy]

Yuck!!
Can you wipe a bit on to white paper and perhaps then can see if its greenish or black?
I'd assume it was algae and clean that sucker out gooooood with bleach.
And monitor your pool chems closely for a little while in case you dropped some into the water.

 

[Divin Dave]

I dont know why anyone would put grease in there either. But - Pool light niches are famous for harboring algae.
That looks excessive from what Ive seen, but it could be. Grab a blob and put it in a box and let it dry out. If its algae, it will dry up like any plant will.

 

[smforte]

When I pulled mine out last year it was similar and diff algae. Scrub it down good with bleach before installing.