Here are my meters that I am currently using for growing:
I’ve had this TDS meter since day-one. It’s a 500 scale meter. Still dead-on in calibration solution, & has an adjustment pot near the batteries if necessary. Only complaint would be is that it doesn’t have auto-shutoff.
-Old Tasco microscope. It works. It’s not great, but it’s good enough for sexing & trichomes. Not really a meter, but it was in my box with the other stuff. Tough to find the replacement incandescent bulbs. Newer models look the same but are equipped with an LED.
-Tetra waterproof temp strip. Good for checking res temps.
-Infrared Pyrometer. This is mainly a shop-tool. Good for checking ballast & light temps, etc. May be good for checking leaf surface temps, but I’m not yet sure about that.
-Kill-A-Watt & a short extension cord. Also, an old noid-light for quickly testing outlets to see if they are hot or not.
New stuff that I recently picked up :
-FutureHorti FH100 Bluetooth PPFD meter. Not tuned for EPAR, just normal PAR. But it has an LED setting, & reads out in PPFD. I’m not sure how accurate it is, but it helps to paint a picture.
-ThermPro Bluetooth Thermometer/Hygrometer. I have one in my clone cab, & two in my main cab. One at canopy height, & one near the roof. It’s nice to be able to check what is going on in there without having to open the cab.
-Hanna PH Checker. Much better than the drops in a test tube that I had been using. I’ve always had PH up & PH down, but never used them because I never knew exactly where I was with the liquid tester. Now I’m able to use those old bottles finally & make down to .1 PH changes on large or small amounts, easily & accurately every time. Only complaint so far would be that this model is not waterproof.
Along with a VPD chart, a DLI guide, & a link to a PPFD-to-DLI converter, all of which are also all-new to me, I feel like I can better dial in my cabs & grows using all of this stuff.