That is weird- the 22" bulb should fit in the 24" fixture-- please take the screen and place it half on or 3/4 on take the UVB place it width wise on one end so the UVB is unobstructed- you can have the screen butted up to the UVB fixture w/ basking lamp next to it - you need the distance for the UVB 6-8 inches directly above the basking decor-- the 5.0 is not strong enough to go thru the screen it's blocking 30% of the rays-- do this till the new bulb comes then post back on here so we can get it properly placed for the T 5 bulb