Didn’t you notice how GregTech handles Molecules most of the time? HNO3 has 5 Atoms total, therefore to get one of each Atom you need 5 Units of HNO3. As for HCl, that is 2, but since we want 4 HCl, it needs to be 8 total. This makes Aqua Regia evenly divisible through its components whenever you have 13 Units of Aqua Regia ready.
It doesn’t stop Oxygen deletion because there isn’t enough Slots for Oxygen (which I clarified I undid the extra Oxygen thing again), but what it DOES do is stopping Water (and therefore Hydrogen) from being generated over time, which resulted in a Storage Problem.