United States Plastic Corp suggests in it's catalog "for UV resistance of PVC Pipe and Fittings paint with a white water based latex paint" I have used pvc pipe (white, schedule 40) extensively for hydroponic gardening and can attest for this working. Units I haven't painted turned brittle and powdery from sun exposure while painted ones didn't. Now doing this to a stub of pipe sticking out of a pond may be a challenge, but it does work.


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