dudeofrude
Aquarium Advice Addict
Guppies, they never stay still!
I'm not a professional photographer, but I am taking a photography class right now. The one problem with having all that external light is that it will be reflected by the glass in the picture. I recently tried the same thing and all you can see are the reflected images in the glass. I really think the light has to come from up above. In fact, the best pictures I've been able to take required me shutting all the curtains, dimming the inside external lights and using no flash. The key for me is the aperture setting.
This just happens to be one example.
Also, ISO down won't really do anything except reduce the lighting in the photo, if you bump it up, it will increase the brightness of your photo, but with the gain of graininess. However, depending on your camera, the grain might not show up for quite a bit. I tend to always shoot around 200 ISO as a buffer. But that's when I'm dealing with portraiture