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Water hardness

What is it? Water hardness refers to the concentration of calcium and magnesium in a sample of water; these minerals are dissolved when water comes into contact with limestone. Hardness is related to alkalinity as they both measure calcium carbonate content.

Why is it important? It is one of the most common elements used to test water quality. Calcium, in particular, is an important part of many of the biological processes in fish.

What does it mean? Have you ever washed your hands in hard water? Did you notice that with hard water, you need to use more soap? You can imagine how having more dissolved minerals in the water may affect the fish living there. Find out what species live in your body of water and what their ideal hardness is. This way, you can track how hardness trends impact your fishy friends.

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Open to Collaborate Notice:

Open to Collaborate Notice: Our institution is committed to the development of new modes of collaboration, engagement, and partnership with Indigenous peoples for the care and stewardship of past and future heritage collections. Learn more about Local Context notices.

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