My birthday is coming up in the next couple of weeks. My dad is looking to buy me an RO/DI system for my tank. Im currently changing 20 gallons of water from my tank every 2-3 weeks by filling up tanks at marsh for 35 cents a gallon. It has turned into a big hassle finding time to do it. I am wondering what is the best and most affordable RO/DI system that we should look into. I would like the price to stay under 175 dollars. If I could have a list of great systems that would be great. By the way my 2 clowns and my lawnmower blenny are doing quite well. The tank has been up and running for over 3 months now. TIA