Green Water-Jungle Pond Offers an easy, effective way to control and prevent the growth of algae. Leaves pond water crystal clear. Helps keep pond clear from algae when used regularly. Pond block is not recommended for lilies or hyacinths. POND BLOCK 1/PK JUNGLE: POND BLOCK 1/PK $2.25 SKU: JUNPB060 Click here to save 5% off of your order! POND BLOCK 4/PK JUNGLE: POND BLOCK 4/PK $9.25 SKU: JUNPB0604 Click here to save 5% off of your order! POND BLOCK 50-EA JUNGLE: POND BLOCK 50-EA $96.75 SKU: JUNPB06050 Click here to save 5% off of your order!