Cloudy pool water is usually too much calcium.

It’s calcium hardness, not your chlorine or pH. Those two keep the water sanitized and balanced, but they don’t do anything about dissolved minerals. Once calcium hardness creeps above 400 ppm (or sometimes lower if your alkalinity is high), the water turns milky or hazy. Think hard water spots on glassware, but in your pool.

Another possibility is fine particles from dirt, pollen, or algae that your filter just isn’t catching. But if you’ve already tried shocking and clarifying and it’s still cloudy, test for calcium. Most pool test strips include it, or you can get a liquid kit. The fix is partial drain and refill with softer water, or a flocculant to clump the calcium and vacuum it out.

Your filter could also be the problem—dirty or undersized. But assuming you’re running it long enough and it’s clean, look at calcium first. Chlorine and pH alone can’t fix what they don’t control.