grid spacing in bullet smoker

I modified a Meco electric to charcoal and am using a weber charcoal ring and grid. I put the water pan on the very bottom of the smoker with ringg directly on top. Here's my ? This model is short, less than 3 ft and designed for only one grid. If I put in a second grid it will be only 2-3 inches above the charcoal ring. Is this too close? Will the fish dry out and smoke too fast to be usable ?
Mike