Way to sanitize hot ponds/check bacterial levels?

[Kenney]

We tested the hotpond water in UH Microbiology lab years ago. In early am
After a nice cleansing high tide, bacteria level was negligible.
End of day, after hundreds of swimmers, much higher levels.
There are endemic pathogens in Hawaiian waters . Can't really bleach
Pacific Ocean. A good immune system can handle most.
Great advise already given. Don't enter pond with open cuts, sores.
Use earplugs if prone to ear infections.
Shower after swimming.
Enjoy!