~Getting serious about water quality~

[orchid-asmr]

Hello everyone!

So in my last post about fertilizers, I'm finally down to get a bit more intracate with water quality.
I bought a TDS meter and a Ph meter, but unfortunately I cant afford a RO system yet.
Have the following measurements for my water (tap):

TDS w/o fertilizer: ~201

TDS w/ fertilizer(brand: Grow More: Orchid 20-20-20):

~251

Ph w/o treatment (no fertilzer or vinegar): ~7.3

Ph w/ fertilizer: ~6.2

Ph w/ vinegar: ~6.4

As recommended I use vinegar to lower my Ph and it pretty much does the trick and havent seen any negative effects on my orchids which is a mixed collection.
just wondering if these are good for watering at the moment.
I also have about half of my orchids in S/H and the other in bark. Just wondering if the TDS are ok mainly, I feel like they are a bit high. I also find it odd that the TDS is only raised by 50 w/ fertilizer. Are these measurements ok or if not is there a way to lower them?

Also I've been looking at Epson salts to supplement my orchids? Any thoughts?