I live in Chicago Il and I want to buy around 3 spear guns. I recently bought a scuba diving kit and now I want to buy a couple of spear guns. I have a couple of questions. I want to know how pneumatic and sling guns work. I also want to know what a spear gun reel is used for. I am probably going to be hunting a fish like turbot but with spikes(in Bulgaria its called kalkan) and smaller fish. I am going to be going to Bulgaria and fishing there. The sea that I will be hunting is the Black Sea (there are murky and very clean waters there). The first gun I want to buy is a real short one.( like SPEAR GUN SEASCUB BY MARES) The other two I want to be one pneumatic and sling. Can anyone tell me which one I should buy. I am looking to spend the least because I'm moving to Bulgaria and I need to buy some other equipment, so the more I save the more equipment I can buy. I also want to know what kind of features I would want on a knife. I read many guides and still need help.