Wow Peat, I didn't know you'd gone digital, I remember you talking about it. Which one do you have and how much trouble and expense, if you don't mind?
Personally Beth, I would buy separate models for pH and EC - if the Extech 500 broke down then you would lose both ways of measuring.
I have always used a Bluelab and I have never had any problems with them, you will find nothing but praise on the internet. Whatever you decide to buy, make sure it does EC, forget ppm as it's a pain to work with. It's not clear whether the Extech does simple EC (the manual is available if you click on the Extech 500 link above, page 5 for the display readout on the manual). It displays EC in the microSiemens scale - confusing, you will have to divide by 1000 to get this in EC...
As for pH, I used to use what Bruce said - an inexpensive liquid and chart, which is perfectly adequate and will do what you want it to.
I am now using a digital pH meter. These are much more fiddly if you are starting out, they need calibrating and the tip must be stored in a special buffered solution to stop it drying out. Once they are all setup though, it does makes reading pH a breeze.
Hi Beth, welcome! I can definitely relate to getting sucked into other things...
No doubt about it, go for the Bluelab truncheon. Looking at the other, better seller from your Amazon link you can get one for $121 shipped which is a great price. It's head and shoulders above any of the others and never needs calibrating or new electrodes ($$$), plus it's waterproof and almost indestructible.
For PH, get one like this for $6 or so. It'll last a long time. Buy local, shipping doubles the price.You can find them lots of places - pet shops (aquarium supplies), hydroponic stores, plant nurseries, etc. I'd love to have a fancy electronic one but even I can't justify the price and upkeep.... Yet.
I don't have a meter, but I pH is as important as EC. And measuring it with test strips costs money, you need to find the test strips, not very accurate / hard to employ, etc. (I do have test strips.)
Edit: I dunno if you want to check eBay as well. Amazon is safer, but...
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