Minute medusae in the millions

On 7/29/2023, while snorkeling in open, clean seas off the windward shore of Oahu, I glanced up and the reflection of the light revealed millions and millions of tiny medusea. I could only make out detail in the largest which were approximately 7 mm round and flat, like a disc. They were gelatinous and had 2 white circles within. The sunlight revealed them, like it reveals dust in a room which is normally invisible (🫥 this is what they looked like except no - and dots were white). Once I noticed them, I continued to see them in every direction for a long time (30 minutes). They stung the exposed parts of my body but were so small the sensations were more like itching than pain. When I finally got through them all, the sensation soon dissipated. Since my return, I contacted Dr. Milton Love of UCSB and explained them to him. I have repeatedly tried contacting Dr Lisa Gershwin in Tasmania, to no avail.