I'm about to set up my first reef tank. I have a Red Sea max e 170, which is 45 gallons. I've been watching the BRS videos and they emphasize adding utilitarian fish early to keep algae and other pests from being an issue. They usually mention clownfish as the first hardy fish to add to ensure the tank is ready, then adding a tang for algae control. Obviously, 45 gallons is not going to work for a tang, so I'm looking for a fish that would be more appropriately sized that would fulfill a similar role. I will also be getting invertebrates for this algae control task, but I'm looking for good algae eating fish.