B&W developing with desalinated water

Hello all,

I recently had some film (Plus-X 120 & HP5) developed by a lab in Sydney that i have used for some time.

I found some marks on my film which i initially thought were caused by lack of wetting agent (photo-flo etc) during the washes or maybe some air bubbles (although i've never seen this in any of the film i have developed nor any of the film that this particular lab had developed for me before) and the lab definitely used photo flo and tapped the tank after agitation.

Then it occurred to me that this problem could be caused by an extreme change in water hardness due to our desalinated water which goes to inner city and southern suburbs of Sydney. Not a problem at my leafy northern suburbs home - but mum will murder me if i attempt anything film related at home.

Has anyone experienced problems with development using desalinated water?
Desalinated water tastes very different to "dam" water so i suspect that it has a vastly different mineral content and therefore potentially is either harder/softer than normal water.

I plan on doing some tests with distilled water vs. 100% desalinated water which a friend at Sydney Water will get for me.

In the US, municipalities are required by law to test water quality on an ongoing, regular basis and to publish reports of the test results. They've got to have some kind of law on the books in Oz to the same effect. If your water quality is a concern for you, why don't you see if you can dig up a water quality report from your waterworks?

The only things I can think of that would be in water which would be detrimental to film developing would be chlorine, bromine, fluorine or one of their byproducts. That information would be found in your municipality's water quality report.