Where can I see bioluminescence around Rio de Janeiro?

Brazlian fellow here.

Ponta Grossa is a beach in Rio de Janeiro. This is the correct location https://goo.gl/maps/nivA7V6jDyFJDT2X8

The bioluminescence is produced by a plankton called Spirogyra - we even have a music that talks about it: https://www.letras.mus.br/jorge-ben-jor/1564857/. I think it will depend of when you visit it, I'm not sure but maybe external factors like polution and heat may affect the visibility.

I have seen it in the Cardoso Island (see https://goo.gl/maps/hkF1hMec7UbK2gEK9 and https://www.cnn.com/travel/article/ilha-do-cardoso-sao-paulo-brazil/index.html) but I'm pretty sure you will find it in Paraty too.

Also, a nice place to visit too is Trindade (https://theculturetrip.com/south-america/brazil/articles/a-guide-to-trindade-rio-de-janeiros-seaside-paradise/), really close to Paraty. The access is a bit dificult (there's a hill called God forbid, roughly translated) but the place is amazing and I heard from friends that you can see the luminescence in the waters there too.

I did find bioluminescence near Paraty, one hour away by boat. In Paraty itself, locals have not reported the phenomenon, but I confirmed it in two locations close to each other:

1. At Happy Hammock, where the owner said the phenomenon happens constantly.

2. At Praia Lula where I experienced it myself on the last new moon night in January.

To get to Praia Lula from Paraty, I had a Portuguese-speaking friend ask around boat captains. We quickly found a boat coincidentally called Luanova ("new moon"), which had an excellent rooftop space for four, and took us there and back (~4 hours total) for 500 BRL.