I guess this is drifting from the thread of the original query but i just wanted to say thanks to all of you for discussing this, as it gives me some much needed background.(posted 8371 days ago)I have used pmk pyro for years now but want to use TF3 fix since it is recommended for use with pyro, maintaining an alkali environment and so on. I recently came accross the formula for TF3 and TF2. I looked at the price of Amonium thiosulphate and noticed that it was much higher than that of sodium thiosulphate. However the formula for TF2 (Sodium thiosulphate..)does not list a dilution from stock (the initial 1 ltr mentioned in the formula..?) to working solution, so asuming it is used at this initial strength, it actually works out slightly more expensive than the TF3 (given the dilution and capacity figures in the formula..). So I decided I would order some amonium thiosulphate and get on with some work.
However my intention was to order 5 kg of it, but I then came accross the comments saying that it is not very stable in dry form.
Any thoughts on this would be appreciated.
Many thanks. Oh I forgot to mention that I do not want to order TF4 from 'The formulary' as I live in the U.K and it would cost silly money for the shipping, hence my exitement upon finding the TF3 formula along with a note stating that it is more alkaline than TF4 anyway..