My 3 kettle set up is this, BK = 25 Gallon, MT = 10 gallon and HLT = 6.5 gallon. I'm not sure if the HLT is big enough. I suppose I could add more water to the HLT but it would disrupt the sparging process with having to get it back up to temp, which I'm fairly new too. I was using an Igloo...