Here is our story- 5 year old waterway 22# sand filter
last summer noticed some sand on the pool floor by the return jets around the same time the pipe that the backwash would flow through also started to leak a steady steam of water, we put a stop-c valve on it, solved that problem, but still noticed some sand and possibly debris coming into the pool. Every time I would try to vacuum to waste it would come out the return jets if I didn't close them off. It was near the end of the season so we just dealt with it and then closed it.
Upon opening we changed the sand and checked all the laterals, one seemed that it could be loose so we replaced it- (the entire set and center tube). Did the backwash , did the rinse, added a new pump since the last one seized, got the chemicals going and the water turned from green to a very cloudy blue.
We attempted to vacuum the debris after the chemicals were level and all the debris (minus what was caught in the basket) came out the return jets.
What could it possibly be now?