My tds meter says on it "calibrate with Nac1". I looked up Nac1 and it is common table salt. So being the cheap fuck that I am, I want to use table salt to calibrate the meter. What ratio of salt to water should I use and what should the tds be of said solution?
Ever been to the hydro store and have them say" tds meters do not need to be calibrated"? I've heard this more than once from people that you think would know, and, why the hell is there a screw for calibrating it if they don't need calibrating anyway right? Well, I don't know about all meters but mine was seriously out of whack. I used it for one grow last year in soil and never checked it, either before or after I used it on my grow. I remember that when I did use it last that my tap water was right around 200/225 ppm. When I checked the tap water last week it was at 325ppm. Well that got me to thinking about my tds meter needing calibrated. I went to the hydro store this morning and got some calibration solution and the meter was way out of whack. After I calibrated it and then checked the tds of the tap water it was at 205. So moral of the story, check your tds meter for proper calibration.
To calibrate your TDS meter, you need some calibration solution. It comes in 1500 ppm strength I think. There might be different ones, but I think mine is 1500 ppm. I have the GH calibration solution. You just put some in a small glass like a shot glass and dip the meter in and adjust it so that it reads 1500 ppm. The NaC1 is the scale of measurement I believe. There is more than one scale used to determine TDS readings. For example my solution has different ppm readings depending on which scale you are using. Most common is the NaC1 if I am correct. I have 2 different TDS meters and one is only able to read and be calibrated using the NaC1 scale but the other one has different modes depending on what scale you want to use. All of this info is from memory off the top of my head, so if something is incorrect I apologize... I'm stoned and tired from yard work and don't feel like going and getting the meter and solution to double check anything. I think it's all pretty much right though. Edit: Haha... I guess I missed the part of your post where you mentioned that you got some calibration solution.... :eusa_eh::new_blackey::thumbs-up:
Thanks Ras, mine also uses the 1500ppm calibration, I also got the gh calibration solution. I had a little burn on the bottom leaves of some seedlings I have going in hempy. Between the meter being out of whack and me getting regular micro instead of the hard water micro (which I also got today ) I had a little yellowing going on. It should straighten out now.
