Last weekend I opened up my filter to clean the sand (same sand been in there for 9 seasons). Swished it around with a broom handle, was careful not to get all the way to the bottom and break a lateral, etc. Before I closed it back up I had to fill it back to the depth of sand recommended in the manual. It calls for a 300 lb capacity, and used at least 110 lbs to fill back to specified depth. So at some point Ive "used up" almost half of the sand.
Didnt seem right to me, but I figured Id fill it back up and run it for a while and see what happens. Sure enough here we are less than a week later and I have sand on the floor of my pool.
Not a whole lot, but clearly its there (grains are too big and "hard" looking to be algae)
Now the question is, how did it get there....first assumption is broken lateral. Is there a way to tell for sure? Would I get a LOT of sand because of it, or just a little? Its not like I have 2" of sand sitting in the deep end, just some here and there in crevices, liner seams, etc.
Could I have overfilled it? I actually filled it to a little below the recommended depth, just to make sure I DIDNT overfill it. Backwashed the new sand for a good 5 or 6 minutes (until the water in the glass sight went clear). That first day or two of running I didnt see any sand in the bottom, now I do.
Multiport valve issues? Not sure how I could tell if that was it. I dont have any water leaking out of the waste port, thats about all I can tell from the outside.
Any other suggestions would be appreciated.