Hello, I was going to set up my 20-gallon-long freshwater tank with a HOB filter, light, and heater already. I decided to go saltwater instead. Should I keep the 20-gallon long or would the upgrade to 29 gallon be worth it? I'm asking in terms of stocking. Would the fish I am able to keep change? Both the tanks have the exact same horizontal dimensions except that the 29 gallon is 6 inches taller. Thanks