This can't be good

So everything has been great with the pool at the house we're renting here. It's been wonderful to be able to take a quick swim when the temperature hits the mid- to upper-90's.

However, last week there was a tremendous amount of rain in Northwest Arkansas which resulted a bit of algae build-up in the pool. I didn't think much of it at first; in fact, I tried to clean it a bit one Sunday morning. A few days later, I awoke to find the pool looking like this. My neighbor advised me not to swim in it.