greens

Michael, years ago I struggle too what could be the best way to take pics of my fish and I think it depends from different factors. Cloudy days are better to get pics. Clean water will help you, if the water has so many particles floating it will as result out focus or distractive pics.

The pic you posted seems that the bottom has algae so that is the reason that you get that color. For sure the best help to get better shots is using a polarizer filter and probably using more manual settings on camera.

I hope it help

orlando