This is a refill for the Barley Ball, a highly effective and environmentally-safe way to encourage clearer ponds. It contains pre-activated barley straw and a float that is seeded with natural micro-organisms. The Barley Ball is safe for fish, pets and flowering plants. Refill the Barley Ball every three to four months Unused refills can be stored in a dry place for two years Made of barley straw Note: If you are ordering this item as a gift and it is the only item on your order, please be aware that there is a picture of the item on the outside of the delivery box