Then err on the side of caution. Don't purchase equipment without knowing if it will do the job. Why spend money twice, once due to the not knowing and then later for what you should have gotten in the first place.

Your lighting will be fine if you do it indoors. Indoors you have far better evironmental controls.

If you want to cool the tank, fans will help a lot. In a greenhouse, some use swamp coolers to drop the building temperature about 10 degrees inside.