I always keep just a little air space in my tanks. I think it's important for folks a bit new at hand development to test exactly how much developer/stop/fixers is needed to cover the film, but not so much as to completely fill the tank jamb full. What I did was keep the lid off my tank and drop in a reel loaded with scrap film. then just pour in enough water to get the level well enough above the film. I like about 3/8" or a bit more. Now take the reel out an shake as much water as you can back into the tank itself. Take the tank of water and dump it into a measuring beaker and check the amount. I use that measurement for all films. Now, for surge marks you mention vs bromide drag? Many beginners to hand development don't know how to tell the difference, for which I will start a different thread.