Feature-Kit Water Feature Cleaner Feature Kit is a fast-acting water feature cleaner. It is suitable for use in stone, poly-resin, plastic, wooden or concrete fountain features. Each pack of Feature-Kit contains 16 fast acting effervescent tablets that will remove unsightly algae and cleans the water in outdoor self-contained water features. Use one tablet per water feature containing 1-5 gallons (4.5 - 22.7 litres). This product is totally safe with birds and animals using and drinking the water but is NOT suitable for use in ponds where fish and plants are present.