I am having a hard time learning how to control my ph balance. I can’t get it stable.
I currently use Apple Cider Vinegar to bring the ph down and Baking Soda to bring the ph up. I'm incredibly careful with using the baking soda though to the point where I go over the ph im aiming for i will dump the water and try again; baking soda is sodium bicarbonate and extended use leads to sodium buildup in the growing medium.
pH down/up solutions are pretty cheap on Amazon though and I ordered a batch last Friday; it'll arrive tomorrow.
Concerning Apple Cider Vinegar: The acetic acid will break down over the course of 24 hours so your solution will drift back towards what it was prior to adding it.
Lemon juice could be used as well but the citric acid also has the same problem in that it breaks down over about 24 hours and you go back to where you started.
This slow change back to alkaline
could be beneficial in some situations I imagine (in the scenario I mentioned in an earlier post about giving your plants micro nutrients)