How do I photograph small fish in a fish tank?

Question

I have photographed different type of fish in different tanks, with or without flash, through the surface of the water or through glass.

However, I think I am missing something. There may be tips or hints that can make working with fish easier.

I photographed small fishes, inch-long fishes, and also Betta, which is a one to two inch long. I do have a macro lens with USM. (Canon EF-S 60mm f/2.8 USM) and flash.

However it is still very hard to focus on the fish. f/2.8 is not an option since almost NOTHING will be in focus. Even with USM and all cross-type focusing points, the fact that the fish is swimming almost constantly can proved to be tricky.

I have observed that certain fish at certain time of day will be more calm. However I can easily shoot 200 photos with only 3-5 satisfactory shots.

I also use flash, this so far seemed okay, the fish were never too disturbed by the flash. I do not think it would harm them either (vs cat with super light sensitive eyes)

So I would try to use f/5.6 or f/8.0 to get more DOF, flash, and use ONE fixed focus point (auto AF point selection will often mess things up as experience shows)

Shooting through glass is okay as long as the glass is flat and smooth (bowl-shaped tank is a definite NO due to uneven surface). Shooting top-down also gives high quality images as long as the water is still.

Still, success rate is pretty darn low.

Any advice from experienced pet photographer that has dealt with small fish, or just aquarium in general?

I like this shot because of how elegant they look, and how happy and free they seem, and the lines their slender bodies form:

My beloved Betta named Bubu who died to a disease after 1.5 years of keeping. [Lightened a little as suggested, didn't have time to clone out the dust yet]

Answer

• Don't use a flashgun. When shooting animals you want to keep them calm and a flash is a great way to ruin that, especially things used to a fairly constant light like fish. Use one or two lamps by the side of the tank but obviously be careful about it. You don't want to fry yourself or the fish.

• Whatever the lightsource is, make sure it's not reflecting directly back at the camera. The water will do most of the work but you might need additional materials to diffuse the light.

• Use a long focal length with a fast aperture. You want as short a DOF as you can get away with or you'll catch tank dust and grime. A short extension tube will help you get a standard lens' DOF even shorter.

• Unless you're going for that effect, don't shoot through the top water surface. The distortion is not predictable.

• Ditch AF in favour of patience. AF against mucky glass will drive you round the bend. Fish aren't that fast so you will get a few shots if you persist.

• I personally don't agree with the white=professional comment. I think for fish, the creamy, dark you'll get shooting through the tank is nicer. It will make lighting harder but that's life. Experiment and make your own mind.

• You can correct distortion from curved bowls to an extent in Photoshop just abusing the lens correction tools.

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