Vincia Maërl Crystal is a natural product with a very low phosphate content. It is suitable for newly constructed ponds and to make cloudy water clear and healthy. Vincia Maërl Crystal increases the joint water hardness and activates the development of microorganisms. It is very user friendly. Sprinkle the grains directly into the pond.Vincia\'s natural products keep the pond free from algae and promote water quality naturally. They are 100% environmentally friendly and biodegradable. Vincia is for the pond lover who would rather not use unnatural means, but would like to enjoy clear water.Also available in 3600g (1330657)