I mix 5 liter batches of XTOL stock solution in distilled water or water filtered though a Brita type filter to avoid potential problems caused by metals, organics, and residual chlorine with prolonged storage. I then store the Stock solution in amber 8 oz. glass bottles with teflon lined caps filled to the brim (no air space). These bottles can be purchased through the scientific supply houses such as VWR or Fisher for about $10-12/dozen.(posted 8597 days ago)Each bottle is a one shot dose to make 16 ozs. of 1:1 dilution XTOL, enough for 2-35mm rolls or 1-120 roll in a small tank. I do not reuse or replentish developer stock solution.
With this technique, I have had absolutely consistent results even with storage >6 months. I've found that the 1:1 dilution provides me with the most convenient development times and finest grain at reasonable cost.
THis may sound like a lot of work, but it is convenient, consistent and predictable.