I've noticed that some of my new passionfruit leaf growth looks different from the older growth:

Given that it's symmetrical and there's no sign of pests, this says to me that it's unlikely to be a virus, bacteria, or pest issue, and is probably a deficiency of some sort. But what? Doing some searching online, the best matches appeared to be magnesium deficiency, zinc deficiency, and manganese deficiency. However, I have to be careful because supplementing of one might cause a deficiency of another!

What do you all think it is, and what would be your recommended course of treatment? Should I maybe try a foliar spray of each nutrient on different leaves and observe the results? I've never made or used a foliar spray for nutrients before, so any tips would be welcome.

I should note that thankfully I went through a hydroponics phase and I used custom mixes instead of premade mixes, so I've got pretty much every known plant nutrient on-hand, even the micros and optionals. :) Or at least I will after my crate gets delivered this weekend. Also, the hot water here (I've been watering with the cold) is sulfuric (volcanic), so if my goal was to lower the pH, I could try watering with it (although I haven't tested its pH yet... all I know is that it clearly smells of sulfur :) ).