If you can get the pH to the 7.4-7.6 range, then any pH-related irritation should be relieved. One thing I didn't mention above, though--often eye irritation is due to combined chloramines in the water (most folks blame it on high chlorine levels, because they smell the chlorine--what they actually are smelling are the combined chloramines that cause the irritation). What are the other test levels on your pool water? FC,CC, CYA, and what do you use to chlorinate with?