Digital testers


I’m looking for a digital meter preferably 3 in 1 (pH, TDS and Temp). Been looking at Bluelab Guardian Monitor. You can see reading 24/7 by checking the monitor, do you think it’s worth the expense? Also do you have any suggestions of 3 in 1 digital testers? Your help will be greatly appreciated.



Blue Lab is well worth your money.

I actually use two separate meters for my TDS and PH.

The brand I use is Apera.

Excellent quality and around the same cost as Blue Lab.

They also offer a combination meter that has excellent reviews.

Here’s a link;

Apera Instruments PC60 Premium 5-in-1 Waterproof pH/Conductivity/TDS/Salinity/Temp. Multi-Parameter Pocket Tester, Replaceable Probe


Actually that is the one I had 2 days ago until it stopped reading TDS, EC and Salinity. Only temp and pH it read the rest just marked 0 and not sure if it was faulty or something so I sent it back. Which Apera you use maybe I buy that and hope for the best


I know you don’t know me but I wouldn’t steer you wrong.
Apera is a very high quality line of meters.

I love mine.

Extremely well built and extremely accurate. :slightly_smiling_face::+1:I

I use this one for my PH;

Apera Instruments PH60 Premium Waterproof pH Pocket Tester, Replaceable Probe, ±0.01 pH Accuracy, -2.00-16.00 pH Range

And this one for TDS/ PPM. ;

Apera Instruments TDS20 Value Waterproof TDS Pocket Tester, Accuracy: ±1% F.S, 0.5˚C, Complete Kit


Maybe one day I change my mind and buy an Apera, but really worries that it would do the same as the one I got


I second the Apera meters. I love my PH meter.


Welcome back @Bogleg the plant is doing great, I agree with you and I will give Apera another chance just bought the TDS20 :stuck_out_tongue:


Well today it arrived but don’t know which one to believe. One is showing 1669ppm the other 2450ppm, the plant is doing great none the less but I’m curious.


only real way to know is to get some kind of calibration solution

I am sure there are some home items that have a set range, maybe some others will jump in with some home remedies…


The Apera came with calibration solution. Did you calibrate it? This would tell you all you need to know.

TDS is the least accurate and most loosely gauged device that we use. You can never get exact values by measuring electrical conductivity of a solution. What you can get is repeatability. The experts talk about around a certain range of ppm. Just FYI.


I have the same meter, the Apera TDS-20.

I went through the steps necessary to calibrate it but it was spot on after testing.

Follow this video to the letter and you will have no issues.

I fully trust the Apera.


That’s what I will buy to be certain on it. Thankyou


It has an EC solution, I did calibrate it and the picture of the reading is after calibration.


That’s the pH tester, on that I have no problems whatsoever but on the TDS one I’m not sure it was worth the expense.


The TDS meters aren’t super accurate but they can give you trends and baselines. I found it very useful during the flower stage in my last grow.