If the color change solidifies on the second drop then the degree of hardness is between the two, so say 6.5 dGH, or somewhere between 107 - 125ppm. If you're using the Hagen kit, or any kit that specifies a 20 time multiplication of drops (most kits go by drops x 17.89), then you have a GH of 130ppm (~7 dGH). Either way your water is considered soft on a scale from very soft to very hard. A GH of at least 3 to 6 is recommended for plant health, so keep that in mind when you mix RO. As it sits, you have a nice amount of calcium and magnesium available.
You won't be able to change pH much by removing what little buffering capacity you have (bicarb / KH), getting to 7 is about all you can do without adding acids from peat etc, which will only add to the total dissolved solids, getting you further from what you really want to do. And it's really not important when you're worried about hardness for livestock where the GH should be your real concern. Even then, it's a rapid shift you want to avoid, most fish etc can be acclimated to whatever hardness and thrive, some even breed. Fish or shrimp will know little difference between 3 or 0 KH. The pH I never mention here because it is a moot point, the reason your tank is not dipping down to 4-6pH like in some wild areas is because it's not filled with rotting waste like those places. Ph that low is on the way to being battery acid, acids and carbonic waste is an entirely different aspect of pH from hardness, which is why one needs to know the difference and concentrate on the important aspect.
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