Okay so I just bought a decent sized kiddie pool yesterday for 12 bucks at walmart. It can hold about 260 gallons of water!! So I REALLLLLLYYYY don't want to have to dump it and fill it every time the kids want to play in it. I filled it up yesterday, they played in it and I didn't dump it and they played in it again today. It is still filled, but it has gotten pretty dirty even though I told them to not get in it without first putting their feet in a bucket of water so they don't put a bunch of dirt in it. Is there anything else I can do to prevent it from getting super gross without have to completely dump it every time? I am not trying to spend a lot of money either... exactly why I don't want to refill it everyday!