I would put off buying a chiller until you're sure it will be absolutely necessary. The initial costs, installation time, and operating costs would make me look to another solution first. That is if it's even needed. The hood likely already has fans in it to help prevent heating the tank from the light. I'd watch the temp for the first week of cycling to see if it's enough. If it's not, see if there's any way to install more fans not to help prevent heat buildup but to accelerate evaporation by air flowing across the water's surface. You can remove a LOT of heat by evaporation. And if you allow your new tank plenty of time to cycle, you'll also be giving yourself plenty of time to try multiple solutions. I'd consider a chiller as a last resort.