You don’t have to own a professional photo camera to take advantage of accessories such as filters. Many common cameras offer the possibility to attach filters in front of the objective.
Out of all kinds of photo filters, one makes it possible to photograph water in its depth: the circular polarizing filter. Polarizing filters allow only direct light waves to pass through, stopping the reflected waves, thus filtering the dispersed light. Not only do they reduce reflections on water or glass surface, but they also enhance the colors. Additionally, such filters reduce exposure with up to three diaphragms, so you can obtain better photos even in the burning noon sunlight. You can see below two photos: the first one is taken without any filters, while for the second one, the circular polarization filter has been used. The difference is obvious, in the second photo the water has much more clarity, offering great visibility and stronger colors.
Both photos were taken with a FujiFilm 6500 camera, and they were not further processed in Photoshop. That’s an old model of digital camera, not available anymore. The closest correspondent is Fujifilm Finepix S6000 fd, just in case you want to know more details. Anyway, Fuji is one of my favorite brands, I like their point and shoot cameras a lot.
I wonder if the circular polarisation filter has the same effect on an underwater camera, but I don’t have the required gear for making this experiment.