Can I switch 28 gallon quad CF to regular 24W single CF?

[150er]

I got 28 gallon JbJ quad CF from friend and want to use it for freshwater. I don't want to use high wattage light so I wonder if I can switch that 105 watt bulb out and replace it for 24 watt one. or I have to switch out the whole ballast.

 

[milesOreef]

Your going to have to switch out the ballast if you want to use a lower wattage CF