It should have a minimum of 250 CFM per SQ ft of area of solution.
Little things make a lot of difference.
The ratio of length to width, type of hood, exhausted on 1,2,3, or 4 sides. Things like a pvc backsplash behind the tank and the tank on either side significantly aids in the fume capture. Wings as little as 3 inches significantly aid in the capture. A small cover that covers as little as 6 inches of the front of the tank significantly reduces the effective area of the tank and can easily be moved just prior to moving the rack into the tank. The hood needs to be able to resist hot fumes.