1.025 or 1.026 is what I aim for. Just as important, however, are all the other water parameters. Ammonia and Nitrite MUST be 0, Nitrate I try to keep below 5 and I shoot for barely detectable, Calcium should be 400-450, Alkalinity somewhere above 8dKH but below 11, and Magnesium 1300 - 1350.
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