I only use the traditional formula. That's picky enough about what papers it likes and unlike Dr. Ware, I do not have problems with mould growing on my Ammonium Ferric Citrate Green. When I first mixed the solution maybe a week or two after using it, some mould did grow into a little floating island in the solution. I used a disposible chopstick and fished it out from the solution. It's never grown back after about the second time of getting rid of the island of goopey mould so I assume i released some sort of deadmould anti-growth stuff.
Then again, I also leave paper coated and out in the open for days/weeks/months and hardly ever have a problem with fogging (only if i've actually left it out exposed to too much light) and everyone else who works with cyanotype say they have to use their paper in a day or two or else they get highlights that turn out light blue and not white
it's really weird but I don't have this problem. I even did it with some buxton paper... I coated it a few days ago, not sure how many, exposed it yesterday, washed it, highlights fine.
I don't use H2O2. Seems like a waste of money and yet another bottle to add to my HUGE collection when I don't really need it... air will eventually work just as well.
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