Well, as I had sand almost constantly in my pool last year, I have removed all the sand, pulled out the lateral assembly and found there to be no damage...it originally had Zeobrite in it. It is a Hayward s210.
Should I put pea gravel in just up over the laterals before replacing the zeobrite I took out?
Should I change from Zeobrite to something else? Is it the problem, is it two small?