Some 700 contestants will be competing in the Ron Jon Cocoa Beach Triathlon this weekend.
A brown algae bloom led to the death of 100,000 pounds of fish in the Indian River Lagoon.
Two water samples were taken from the Banana River earlier this week and showed low levels of fecal coliform.
But Cynthia Leckey of the Florida Department of Health in Brevard County warns the test is only a spot check.
“That does not sample for the algae bloom or bacteria that may come from the decaying fish”
Leckey says there is no advisory warning swimmers not to enter the lagoon, but there’s always a risk.
The Florida Fish and Wildlife Conservation Commission is taking weekly samples to monitor brown algae growth and bacteria levels in the lagoon.
The swim is a quarter-mile long and starts near Cocoa Beach High School.