That is a 17" deep tank, and standard aquarium glass will block about 15% of light allegedly. If you have a deeper tank, I would buy the highest wattage you can afford, and hang it high/shade it out as needed-although I don't think you would need more than the 50W in a planted tank.
From looking at that tank though, that is not low light, at least medium in my eye-but I suppose a par meter is better than the eye test.
|