Test Kits for Testing Water in Saltwater Aquariums

You can't visually determine the pH balance of the water in your saltwater aquarium. To maintain healthy levels of chemicals and minerals in saltwater aquariums, you have to test the water, and to do that, you have to buy test kits. Here's a general guide for purchasing test kits for your fish-only or reef tank. As your tank becomes more complicated, you can always add to your test-kit collection.

Test Kit	Fish-Only Tank	Reef Tank
pH	yes	yes
Ammonia	yes	yes
Nitrite	yes	yes
Nitrate	yes	yes
Alkalinity	optional	yes
Dissolved oxygen	optional	optional
Copper	optional	no
Phosphate	optional	yes
Iodine	no	optional
Calcium	no	optional
Silica	no	optional

Test kits are made so you don't have to be a chemist to use them. Although a couple of methods have been developed, the most common involves adding drops of the test chemical to an aquarium sample that changes the color of the water. You then match the watercolor with that on a color chart, which tells you the correct level of what you are testing.

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