Since I just finished my 4x2x2 tanks, I needed to figure out which bulb/fixture combo would work best for this size tank.
Well, quick and short, I'm going with the 22" even though the tank is 48" in length. This is less than half, but it was the only way to get some areas to have a UVI level of 0.
Only about the furthest 3-6 inches of the tank have a UVI of 0 with the 22" 10.0 T5. So it's really quite a small percentage when taking into account the whole enclosure.
With the 34" even the farthest area from the bulb had a UVI level of 0.5-0.6. Even without a reflector on.
So, If ones goal is to provide a truly proper UVB gradient in a tank, it appears that for 4x2x2's the 22" bulb is the way to go, not the longer one.
And this is of course with the tube almost butted up against one side, I'll add pictures tomorrow.
-Brandon
Well, quick and short, I'm going with the 22" even though the tank is 48" in length. This is less than half, but it was the only way to get some areas to have a UVI level of 0.
Only about the furthest 3-6 inches of the tank have a UVI of 0 with the 22" 10.0 T5. So it's really quite a small percentage when taking into account the whole enclosure.
With the 34" even the farthest area from the bulb had a UVI level of 0.5-0.6. Even without a reflector on.
So, If ones goal is to provide a truly proper UVB gradient in a tank, it appears that for 4x2x2's the 22" bulb is the way to go, not the longer one.
And this is of course with the tube almost butted up against one side, I'll add pictures tomorrow.
-Brandon