Lighting for a 5.5 gallon

[skeeters]

I'm moving some emerald crabs, cheato and live rock from a 1.5 gallon tank. Going to a 5.5 rimless but having problems with lighting. I have a hampton bay desklight which is 6500K 27 watt pc bulb.

 

http://www.amazon.com/Sunlight-Lamp-Silver...d/dp/B0012RVX88

 

I'm not sure if the bulb can be changed. I tried to use a 20 watt coralife screw in but it was too long and lamp fixtures didn't work. I can't hang over it cause of location.

 

So I need a desktop type lamp or a clamp on for rimless. Any ideas? I might just keep it all macros. If so, would certain corals like buttons or shrooms survive under 65K?

 

Thanks. I got everything figured out but the lighting.