Does ABS pipe give off a toxic oily residue? I have a fish pond and each year for the past two years my fish have died. The only difference during the past two years from previous years is my having replaced the PCV pipe within the pond with ABS pipe because ABS piping is black and is not visible when looking into the pond. I have some pine trees also around the pond that are slightly bigger now that could, perhaps, be giving off some pine oil. But, I've never had any oily film on the pond prior to two years ago, and the fish were healthy in the past. I'm thinking of removing the ABS and returning to PVC.

Does ABS pipe give off a toxic oily residue?

The manufacture says no, Read what he has to say below.
Freedom from Toxicity, Odors, Tastes
ABS and PVC pipe and fittings systems are non-toxic, odorless, and tasteless. The National Sanitation Foundation lists PVC for use with drinking water.
However I see The National Sanitation Foundation lists PVC for use with drinking water. Nothing about ABS.
We used ABS for drainage back in the 60's but switched to PVC in the 70's. We haven't used it since and never in potable water for the home.
Change back and see if it doesn't improve. Good luck, Tom

I am a chemist, not a plumber, but I have worked in the paint and plastic area for 20 years. I highly doubt the oil is coming from the ABS. I would look for another source of the oil.