What To Do With Water Hardness?!


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So hi. I have 2 cherry shrimp, 6 neon tetras, and a patch of micro sword. I own a 10 gallon tank. I would like to install Brazilian pennywort as a mid/background plant. I heard that it slows down growth in softer water. Should I harden it? How? And what new fish should I get for this hard water? I am planning to get the optimal 4+ inches a week from the pennywort, and apparently hard water helps that a ton. I WOULD like new fish as well, as around 6 inches of fish just jumped out of my tank. Any suggestions? Thanks!


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3 years
Do you know your current hardness?

Hard water is one of the many factors that makes a plant grow faster, and isn't really the most important factor either. Lighting is what makes plants grow fast, but more light means you'll need more fertilizer and CO2, or else algae will take over. Hard water acts as a fertilizer in a way, because it's the magnesium, calcium, and potassium that makes water hard, and those are three very important plant nutrients.

Also, neons are evolved to soft water. Drastically increasing the hardness isn't something I'd recommend for them. Soft water fish living in hard water have been shown to have higher mineral buildup in their kidneys post-death. Also, the inch per gallon rule isn't very good (a 20 inch fish can't go in a 20 gallon) and I'd be cautious about what fish to add.
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