2 things, constantly too wet and starving hungry.
Water, then only water again once the top inch or so has dried out.
Never water just because you feel the need to "do something".
Continue using fertilizers and this will help stop the problem getting worse.
In soil, a schedule of plain water/feed/plain water/feed......should work in this situation for you.
This means only feeding every 7-10 days.
Some of the leaves may recover slightly, but generally, once this damaged, they stay damaged........but I think you should focus on stopping things getting worse rather than trying to "fix" anything.
Remember too, what is showing in the leaves now, is a direct reflection of what was happening in the root zone 2-3 weeks ago, so obviously there will be some time lag between starting feeding and seeing results.
Calcium won't hurt, but is not the answer to your current issues, lack of general feeding is your issue.