Ok bulb strength on this is way too high for a single bulb fixture. You need either a 6% arcadia or a 5.0 zoo med uvb bulb. If your fixture is a 24 inch then the bulb for it is a 22 inch. Bulbs are 2 inches shorter then the fixture.
IF you use this bulb there has to be a 12 inch drop between where the fixture sits on your cage and the highest point baby can get to or the cham will be over exposed with UVB> Using this you will lose all of your upper area of cage.
When you switch down to either a 5.0 or 6% bulb the distance would be approximately 9 inches for proper UVB exposure.