In February, the waters in Columbus will be a bit cooler, (mid 70's) than what they are in the summer months. For some folks a 3mm suit is fine; however, if you have a tendency to get cold or are doing morning and afternoon dives over several days, a 3mm fullsuit with a vest or a 5mm fullsuit would be more appropriate and ensure that you have fun dives without getting cold. Dive safe.
I second Dad's recommendations. I don't think a 3mm would be enough in February. I'm assuming you're diving with booties, but if you're in full foot fins, I would add some thin socks. Note that you can't wear gloves at CI for environmental reasons, so you need to think of heat protection on other places. I might also add a hood or one of those beanies.