Hi Aquatron,
I'm having issues with the spray paint becoming dull and not staying glassy - how many coats do you use? What's your procedure?
I've been trying to paint the whole setup (red for drain, blue for return). I've sanded and washed all of my fittings and pipe, then dry fit. I'll then glue them in place (with lots of unions), let it dry, tape off threads/handles, and spray paint the whole section the color I want. I've been doing 3-4 light coats (spray paint only, no uv sealer) with about 3-5 minutes wait between coats.