Another hydro Cal def. Self diagnosed as pH, but what to expect from recovery?

I have the startings of what could soon be an evil calcium def in my first hydro grow (experienced in soil), and think it would be due to 5.9-6.0 pH, so dropped down to 5.6-5.7 to help take up. Using biobizz grow, and gave some Hesi Powerzyme for trace elements, but not sure if these contain any or enough Ca. Alos, using tap water left to "air" for 48 hours, which I would have thought contained Ca as well, so can only presume it's pH.

Hoping that the pH change will sort it, as I can't afford any Cal/Mag for a week or so.

Should I expect the leaves to regain a healthy colour, and the necrosis spots to repair, or just no new signs of def??

Would really appreciate any help

yeahh old leafs will still show but new leaves shouldnt have it

thanks for your time, i'll keep my eyes on it

The damaged leaves will never repair, but new growth should be healthy.