If you hate math and don’t want to track dates, here’s a cheat: replace your cartridge filter every spring before peak swim season. For sand, set a reminder every five years. For DE grids, check them annually and replace as soon as you see wear.
And please, please, don’t be like Dave. He spent the whole summer shocking and vacuuming, trying to fix water that a new filter would’ve solved in a day. He finally replaced his filter in August. The water cleared in four hours. He admitted, “I’m an idiot.”
So how often should you replace a pool filter? Whenever it stops doing its job, and definitely before you invite the neighborhood over. Your frog friend can find a pond elsewhere. Trust me—your pool, and your guests, will thank you.
