I always put the water on the cooler side. UTH should be more then enough if you get the appropriate size, then again it all depends on the temperature of your room. I have a UTH on both of my tanks, probably not the best size and they don't heat the tank to the needed temperature so I use overhead fixtures also, but down here we don't have a problem with humidity, overhead fixtures suck up humidity. UTH are a must period for the humidity sake, but if for some reason you get the size you need and it doesn't heat the tank properly, then you can always resort to Heat tap on the lower sides to give additional heat.