Lures diving in the water, studio shot with two lights on a blackbackground

Yesterday a friend showed me an image of a lure swimming in the water on a black background. This was some sort of relief because when I did my first test, I had to quit the idea of using a black background because reflections flare and light spills were everywhere. So yesterday, with renewed energies I set up my studio and the first thing I did, in addiction of putting my black vinyl background, was to cover 2 sides of the tank with black cardboard.
I also got rid of the large lights, any umbrella or softbox would send too much light out of control so I decided to go hard and small. One SB800 was set with its dome and the other with a Honlphoto Grid one of each of the narrow side of the tank, power settings changed a lot during the session so is hard to tell which has been the most commonly used. I also switched the main light from one speedlight to the other, again hard to tell some sort of rules.
Once everything was set the first test shots were suggesting a decently dark background that could be easily manipulated in Lightroom, giving me the proper black I needed. Now I needed to find a way to focus on the lures, so I put one in the middle of the tank, same distance from the two longest walls, and hoped for the best. I obviously took the focus with the lure under the water, I have read somewhere that the liquid element not only increase the magnification of the objects but also swift the focus point.
Since I was on my own I needed something that could help me moving the lures, for this reason I tied them to a thin fishing line of the length of the longest side, with a weight on the other end. I could pull the lure to one end of the tank, the weight would lift up to the opposite edge and once I released the lure the weight would pull it to the other side … gravity!

I shot with the camera parallel to the wall of the tank, with a bit of angle from above, a pretty high angle, and a very low one and achieved different results. Parallel or with a small angle worked fine, the images are sharp when the focus is on the money, but from a very high or very low angle, like in this image, sharpness and focus became an issue and I believe that is because of the thickness of the glass, that would create refraction and a bit of distortion. I’m not an expert on this matter but I believe I’m not far from the scientific explanation.
I made so many shots that my D7000 was smoking, well at least it was very hot and sometimes needed a break to process the files. The SB800 showed how good they are for the hard work, not a single complain, never stopped, always recycling fast and with just one set of batteries. Some intensive processing in Lightroom followed, I needed the blacks to be black, and the lures to be sharp and well exposed. It has sure been a challenging experience, I have made an unlimited number of mistakes and probably none of the images is really good, but it has been my first step, hopefully I’ll do it better next time.