Protect marine fish and invertebrates from unsafe water conditions with API SALTWATER MASTER TEST KIT. Fish waste, uneaten food, plant refuse, and other organic compounds can create harmful levels of ammonia, nitrite, and nitrate as well as cause drastic fluctuations in pH. These unhealthy conditions can result in fish stress, gill, and tissue damage, and even death.The API SALTWATER MASTER TEST KIT accurately measures these four saltwater parameters that are key to keeping your aquarium healthy. It includes six bottles of liquid test reagent, four glass test tubes with snap-tight caps, a holding tray, and a step-by-step instruction booklet with information on how to correct unsafe water conditions. Simply fill a clean test tube with 5 ml of water, add the appropriate test drops and compare the results with the color chart. Then follow the recommendations to modify conditions if action is needed.In order for fish to thrive, water must be similar to that which could be found in their natural environment. Poor water quality can cause fish stress, illness, and even loss. The most common water quality parameters are Ammonia, Nitrite, Nitrate, and pH. All may vary over time and all are invisible to the eye which is why it is important to test weekly. Testing aquarium water weekly will aid in keeping your most important water parameters within the proper range for your aquarium.