I too use Protectan (or simply butane/propane gaz) where I cannot use different bottle sizes (i.e. color chems like for E-6). For Xtol, I prefer the approach of having different brown glass bottles (pharmacy type) *fully* filled. No air is better than trying to replace it by another gaz. Another point, Xtoll keeps very well when ... dry in its original pack and it's pretty cheap (B&H: 10$ / 5 liters), so I'm not really worried if I need to dump a small part of it ... Claudio Bonavolta www.bonavolta.ch ----- Message d'origine ----- De: Peter Badcock <peter.badcock@xxxxxxxxx> Date: Fri, 6 Jan 2012 00:27:10 +1100 Sujet: [pure-silver] Re: De-ionised versus distilled water for XTOL À: pure-silver@xxxxxxxxxxxxx Thanks Cor,I put my 5L of XTOL stock into brown airtight bottles too. Each time I use some from a bottle I spray in some of Tetenal's Protectan Antioxidant agent.I'm aware Kodak put chelating agents into XTOL, but I want to squeeze as much life as possible out of the XTOL by using water that has minimal iron and copper in it to start with.rgdsPeter On 5 January 2012 23:47, <C.Breukel@xxxxxxx> wrote: Hi Peter, Cannot answer your question on de-ionised water, but I seem to recall that Kodak puts chemicals in Xtol so mixing with less than pure (various tap waters) water has no ill effect on the developer (I guess chelating agents such as EDTA or so).