Hi Franie, this is Peggy. Here is the information I found on fixing resin sinks, sorry wish the news was better. Cleaning a composite resin sink... - Forum Thread - Tech Advisor
Oct 4, 2017 - 11 posts - 5 authors
Anyone living in a hard water area with an resin sink and know how to ... You have damaged the surface (it's become pitted) and the problem is insoluble. ... These are ideal for removing stains from cups etc and also from a ...
You really can't. Just get clean as you can.
Try bleach on a sponge and let it sit on the stain for like an hour so it should it should take it out
Thank you...I'll try it. Its just too bad that plumbers charge more to install a sink than what the sink was purchased for.