Healthy Ponds 50177 Rain Barrel Water Cleaner Dispenser with (2) 30-Day Treatments Prevents poor water clarity, odor and floating or suspended organic matter by consuming excess nutrients for improved water quality and clarity Treats 5 to 150 gallons; two 30-day refills provide 60 days of treatment Each refill provides 24/7 water conditioning for 30 days Saves time and effort, with no mixing, measuring or mess Natural bacteria and enzyme blend is safe for humans, pets, fish, birds and plants