Rowalith W 9-15mm Media 6Kg Be the first to review this product.   Large media of 9-15mm grain size ideal for larger calcium reactors, due to the large grain size it will resist tracking of water through the media often experienced when running small grain sizes in larger non fluidised reactors. Rowalith W is mined from ancient coral beds and provides the correct levels of Magnesium for your hard corals. Price : R1,800.00R1,600.00 Discount : R200.00 (11.11% off) Qty :- 1 2 Add to Cart IN STOCK, (Only 2 left in stock) Usually Leaves Warehouse the Next Business Day. Allow 3-4 Business Days for Delivery.