I've made many hundreds of cyanotypes in central Florida where the water is quite hard. After testing many papers, I've settled on Arches Aquarelle water color paper as a decent paper that gives good results. You should be able to find that readily. I add 1/2 gram of oxalic acid (wood bleach at the hardware store) to each 100 ml. of solutions A and B to help counteract the effects of alkaline water. Have you measured your water's ph level? That would help offer meaningful advice and allow meaningful comparisons to other's working conditions.
Originally Posted by quiver