Remember:

Algae itself isn't dangerous--you can swim in lakes, rivers and ponds with algae. But algae forces your chlorine to be consumed fighting it, leaving you no chlorine to fight the bad biologics--water-borne diseases and bacteria. It strips your pool of its defenses against the serious stuff. That's why you have to get your CC to <.5 and your FC to hold and not drop precipitously.

You can swim in higher chlorine levels (relative to your CYA level) just wear older bathing suits so if they fade it's OK.