AquaChek High Range Phosphate Test Strips Tests for: High Range Phosphate This quick and easy test is ideal for use when phosphate levels are high. This will help you determine which phosphate treatment removal methods are appropriate for your pool. FIND AN AquaChek RETAILER Product Demos FAQ Product Information Recommended Products Product Information Phosphate: 0-50 ppm Bottle. High range phosphate. Recommended Products AquaChekSilver AquaChekNitrate/Nitrite