Honestly, the ducks are nasty. They poop in their pool and make it all nasty in less than a day. I dump it every other day and refill with clean water and you'd think they never had clean water before. They go nuts bathing themselves and playing in the clean water. I love having ducks, though! So, tell me what you do with your duck pools. Do you empty and refill your pool every day? Do you just top it off with more water? Those of you with bigger pools, how often do you empty it? I know people with concrete pools that are quite large. They only clean them out once a year. The bottom of those pools must be NASTY. What do you do?