growing algae fast on pvc

I was just made aware of an old Tennesse trick by a local good ol' boy. He said if you pour buttermilk on the pipe and let it completely dry in the sun, it will grow algae like a banchie! Must be the proteins and stuff left over in the film that brings the algae in to eat/grow. Give it a shot, can't lose anything. He says go to the store and get the expiring stuff for free!

Algae are plants. They make their food from the sun.

Roughing up the pvc with a wire wheel or a palm sander will get them a little quicker purchase.

I'm saving my buttermilk for pancakes and biscuits.