RO is devoid of minerals, so you have to add them back. Generally, this gives us better control for things like shrimp.
GH booster adds back calcium and magnesium. Macros will be Nitrates, Phosphates, and Potassium - and I don't believe most city tap water contains those though some tap and well water do contain nitrates.
Yea I got a small reading of nitrates from my tap water via the API fluid test. No ammonia, nitrite. Just a hard water at 7.5.
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