exactly! i believe the mixture is 1 oz. crystals to every 1 gal. of water. so just buy a gallon of distilled water, put in an oz. of crystals and let it sit over night.And if you don't want to waste your money: http://www.water-sorb.com/store.php?crn=206
Buy it dry and make it up as you need it.
2lbs of the stuff is a bit over $20 shipped and will last your average keeper a couple of decades, probably longer. I bought about this much from the garden department of home depot almost 5 years ago and still have yet to make any real dent in it.
Do NOT use distilled water for watering anything. If you are paranoid, buy filtered or spring water (or buy a filtration system) but distilled water is pretty much about the worst thing you can ever put into a living system. Any time you use distilled water you are leeching nutrients from the organism being subjected because of basic solute gradient issues in biological systems. BTW, tap water is fine in 99.9% of municipalities.exactly! i believe the mixture is 1 oz. crystals to every 1 gal. of water. so just buy a gallon of distilled water, put in an oz. of crystals and let it sit over night.