24" Light

[Incitic]

Can anybody tell me the max wattage you can get out of a 24" bulb?

 

[daza]

A standard 24 inch long T8 (1 inch diameter) fluorescent tube is 18 watts.
I've also seen some advertised as 20W (Aqua Glo).

A 55 watt Interpet T5 is 21 inches long.