I am planning on keeping platys. But I am caught up with some conflicting information, and I am unsure what the truth is. What is the optimal GH range for platy fish? Because I have a book about aquariums and fish and for platys it says "hard (100-150mg/L (5.62-8.43 dGH)), and then Wikipedia says "moderately hard", another website says 10-25 dGH, another website says "soft to hard", (dGH): 12 - 18°N, is the "N" a typo or does it mean something? the next one says "medium to hard dH range: 10-28". What GH level do yous have in your platy (maculatus and variatus) tanks? Also I have read that when they say "hard" or "soft" that they are talking about GH and not KH, but can it be KH sometimes? All help will be completely appreciated, thankyou.