Bleach in a fountain?
 

I have read that I can use bleach in an outdoor fountain (no plants or
fish) to remove algae. Does anyone know the amount of bleach? Also,
I have a dog and want it to be safe for him as well as wildlife.

Finally, would I just add the bleach and wait for the tons of algae to
go away or do I need to clean it out first. Cleaning first is a
little difficult because the fountain is a natural one we made with
lots of rocks (as opposed to the concrete store-bought type).

Thanks.