Quote Originally Posted by tenax
you're welcome to disagree, carl...i'd rather be safe than sorry...most of my motivation to change the sand was based on how long the sand was in the filter given it was prior to my ownership. ...
I would say this is the key: changing the sand because of the prior ownership. You have NO idea what goop and garbage that previous owner tossed in. I hadn't realized that. By all means, then, changing the sand is appropriate.

I'm coming around to the view that if you are not the first owner of a sand filter, then upon acquiring it, the first thing you should do is change the sand. And since you're doing it, check the laterals. Kind of like changing the oil immediately after buying a used car.

But if you are the original owner, and have followed the guidelines of pool and filter care we suggest, from day 1, then I believe you have no reason to change your sand.

Since I get such excellent results from my 4 year old sand, with a little DE added, I see no reason to either change my sand or go to Zeobrite.