400g - 2kg - 4kg - 8kg. 8kg = 20 x 400g Bags. 400 Grams = 1 x 400g Bag. 2kg = 5 x 400g Bags. 4kg = 10 x 400g Bags. The ceramic material will withstand any chemical reaction and is suitable for both Fresh and Salt water Fish Tanks and is perfect for use in Internal / External Pond & Aquarium filters.
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