Lmao i am a cheap bastard but not even i am that cheap! I paid $20 for my quart of ph down and literally takes 5 drops to make a gallon drop almost 1.5ph! For the most part tho i stopped checking solution ph! I checked first gallon for the nutes i am currently using at it put the RO water at 6.8ph which is good enough so i just assume all the other jugs are similar! I do have a soil ph probe tho so i can check soil ph easy to make sure not drifting all over!
Gotta remember, I've got 3 55 gallon drums in my yard I'm growing cukes in, plus another ten 27 gallon totes for tomatoes and peppers. Lots of water I have to PH. I've gone through a pint of General Hydroponics PH Down in about 2 months. My water here sucks. I PH'd my tap water, and it was 8, and that was BEFORE I added the silicone, which takes it even higher. And I added 35 grams of potassium silicate to each of the 55 gallon drums, so its going to take quite a lot of acid to bring that PH back down to 6.
I just ph'd a gallon of water to water my tent, and it took 6ml of my homemade sulfuric acid after I added 3ml silica.
So I'll need 6ml x 50 = 300ml of my new acid for each drum.
Glad I bought a graduated cylinder for measuring!