I've been getting sand and small debris coming out of my one return jet this summer and have been dealing with it by sweeping it into a pile and vacuuming it until I've finally had a chance to take out my sand and inspect the laterals. After close inspection they all seem to be fine, no cracking or anything that looks out of the ordinary with them or the standpipe ("manifold assembly"?). Believing I've eliminated that as the culprit, I've turned my attention to the spider gasket in the multiport valve which doesn't seem too bad but when I rub my finger along it there is some crumbling of the rubber. Basically I'm wondering if I'm barking up the right tree and also while I have the laterals disassembled I'm wondering if there is supposed to be some play in the connection between the lateral and the assembly it screws into (I tried attaching video but either it's too large a file or file extension not supported). The laterals are not fully threaded but rather have notches that require a quarter turn to lock into place. Other idea is the sand I'm using is too fine (though I did buy pool sand from pool store, but don't remember exact specs).