I have a plastic (resin) tub in the laundry room and after about 8 years of use it's pretty well stained. In fact, the only thing that got to the stains was 0000 steel wool. Now, how do I keep the tub from staining that badly again (yea, I hear ya with the, 'rinse it out and do periodic cleaning'. Well, it's not likely so I'm looking for a sealant for this app. TIA!