What kind of 75w light? PC's don't come in 75W. Neither do VHO, MH, or T-5.
Those are the types of lighting that's good for maintaining a reef tank.
There are 75w PC shop lights that folks use for their fuges to good effect for macro growth, but they're the wrong spectrum for corals.
The dimensions of this I found made it about 24g total. I couldn't find the dimensions of the separations. So I don't know what the actual center area would come out to be. I know I can put together a 20g tank with a HOB fuge and small skimmer for about the same amount of money.
I don't want you to take this as me trying to talk you out of it. $115 for one of these fuges is a great deal, and you can always use it on a larger tank at some point in the future. I think it would be an interesting looking tank. I just don't see that you'd be saving any money using one.
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