I actually have a 75 gal. right now that isn't being used for anything. How much harder is saltwater than freshwater. I have plenty of time to work with it. When i'm not at work i'm at home cleaning or building cages for my snakes anyway. If it is that much harder then i'll go fresh in the 75 and get a larger one down the road for salt. In either case what equipment would i need to purchase and what are some good suggestions on compatible colorful fish? Thanks