Quote Originally Posted by 14me2
After a while there will be little channels of sand in your filter, this is not doing anything to filter, (it looks like ants live in there) but allowing it to make it right back into the pool. If you treat your sand at the beginning and end of season, then yes your sand will last longer, but most people don't and relaly it is just as easy to go ahead and change it yearly. Sand will harden and the the water will have to flow somewhere, so it makes the channels....
I've used the rinse option for this....stirs up the sand....then resettles in filter option. Do you have this option on your sand filter? This will be my 3rd season w/ pool and I think filter is doing a good job. I did treat sand following 1st season at closing/draining of pipes, but not this year as I kept everything online and cycled pump when temps were below freezing.

CaryB