Basicly the wattage of a PC
bulb can be determined by its lenght.
96W bulbs are approx 34" in lenght
55W/65W bulbs are approx 22" in lenght
36W bulbs are approx 18" in lenght
13W bulbs are approx 8" in lenght
I cant help with your other questions as I have not owned a CSL hood.
The 10K bulb should appear alot brighter than the actinic bulb so ya it sounds like it needs replacced. Sounds like you got this used. If this is the case then you might wnat to just replace both bulbs as they should be replaced at least every 12 months.