Its been years since I used a pool. Now mine make their way to the pond we have. This does cause predator issues but its more natural. When I did use a pool it was dirty daily about 1 hour after I filled it. After 2 weeks I waited awhile to change it, ducks didn't seem to care. Any vegetation or bugs that make their way into the water the ducks will enjoy. If your worried about a clean pool for looks good luck, that's near impossible w/o it being confined w/o any type of soil in the pen. Even then they will probably find a way to get it dirty, its what they do.
I think I waited until there was about an inch of mud or debris on the bottom of the pool, floating debris I just skimmed off, before changing water.
I think I waited until there was about an inch of mud or debris on the bottom of the pool, floating debris I just skimmed off, before changing water.