Blagdon Pondseal V8 is a clear polyurethene sealer which when applied to concrete will both waterproof it, and prevent toxic substances leaching into the pond or water feature.V8 Pondseal does not require any primer and is ideal for new concrete ponds and water features, as well as re-sealing old concrete. The benefits of this product over other similar products includes quicker drying times, greater ease of use, increased coverage per litre, and a reduced applying time due to less coats being required.