For as often as your going to use it just buy a little bottle. If you calibrate to distilled you will be off a little bit at 1.026. If your going to make a solution you would need to have something that can measure AT LEAST to the .1gram. And preferablty to .01 gram, or better yet .001 gram. Also your fluid measurements would need to be within a couple off cc (for a 250cc bottle), to be accurate. Save yourself the uncertainty in your measuring ability and buy a solution. Well thats my opinion anyway.
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