BACKGROUND KNOWLEDGE ALL LIVING THINGS NEED WATER TO SURVIVE USEFUL SUBSTANCES INCLUDE DISSOLVED OXYGEN SOME HARMFUL SUBSTANCES INCLUDE NITRATES AND PHOSPHATES NITRATES ARE NEEDED BY PLANTS AND ANIMALS TO BUILD PROTEIN, BUT TO MUCH CAN BE HARMFUL PHOSPHATE IS AN ESSENTIAL NUTRIENT FOR PLANTS AND ANIMALS GROWTH, BUT CAN BE DANGEROUS IF THERE’S TOO MUCH pH IS A MEASUREMENT OF THE ACIDIC AND BASIC QUALITY OF WATER TEMPERATURE AFFECTS THE AMOUNT OF DISSOLVED OXYGEN IN THE WATER
