To shock or not to shock??

[CarlD]

Richard, of course, is right. As long as algae is blooming in your pool, your chlorine will be consumed killing it. With no chlorine you have no way to kill bacteria. That's the real danger. As far as I know, algae itself is not dangerous, but it "sucks out" the chlorine you need to protect you from the dangerous stuff.

Bather waste sounds disgusting but it includes less gross things like sun-tan lotion and other cosmetics, anything that's present on the skin, as well as the less pleasant things.

[chem geek]

The only direct danger with algae, other than the annoying higher chlorine demand, is that it can be slippery and if it is clouding the pool it can prevent you seeing someone drowning at the bottom.