Chiller Sizing

[Parker]

I'm trying to decide if I will need a chiller and what size I should purchase if needed. My tank (265) is in the basement, the basement never climbs over 20C.

I will have a full canopy to the ceiling on my tank with 3x400w bulbs. I have ventilation already in place above the tank in the ceiling to the outdoors. Will I need a chiller or will I be able to get away with fans over the sump?

Thanks