Join Date: Jan 2008
I would just make it again, if you have the reagents to spare.
If you have access to an analytical scale (which I assume you mean by "laboratory scale"), then you can scale it down from 6 grams to (say) 0.6 grams and make 500 mL of 40 dkH water only.
From there, just take 100 mL of the 40 dkH water and add to 900 mL of DI water to get your 1 L of 4 dkH water.
You probably do not need a Pasteur pipette, as it will not add any more accuracy if you are using graduated cylinders only. The only time it may be useful is if you were using volumetric flasks to make up your solutions.