The use of light in the aquarium will allow you to use higher shutter speeds and freeze uncooperative fish. Shooting with ISO only is fine for developing an understanding of how the camera works, but having lots of light makes a huge difference.
I use 2-3 speedlights in my 8x3x2 tank. I use one speedlight in tanks smaller than ten gallons. Depending on the fish I'm shooting, and at what depth they are, I use the speedlights at about 1/4-1/8th strength, and all my settings are set manually.
I use 2-3 speedlights in my 8x3x2 tank. I use one speedlight in tanks smaller than ten gallons. Depending on the fish I'm shooting, and at what depth they are, I use the speedlights at about 1/4-1/8th strength, and all my settings are set manually.



