What is Reddit's opinion of Embryant Digital PH Meter, PH Meter 0.01 High-Precision Pocket Water Quality Tester, PH Range 0-14, Suitable for Accurate Testing of Drinking Water, Aquariums, Swimming Pools, Hydroponics, yellow?

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> When would I need calmag?

Well you absolutely need CalMag but sometimes there is enough present either in the soil you’re using or in your water to at least sustain the plant for the first few weeks. But it’s often not enough. After NPK and Sulfur Calcium and Magnesium are the next most important nutrients for a plant. Here‘s an article that goes into more detail and should explain everything you need to know

Now about PH, you can think of it like a temperature scale. On the low end things get very acidic like lemons for example and on the high end things get alkaline like baking soda. A plant needs a certain PH range in order to absorb nutrients. If you buy a premixed soil don’t worry about the PH of it. But you need to worry about the PH of the water you add. For soil it should be between 6.2-6.5 ideally. In that specific range all nutrients can be absorbed by the plant easily. If you drift to much from day to day it will stress the plant. If you stray to far from those values the plant can die easily.

In practice this means you get water, check the PH of it with a digital meter and depending on where you started you either need to up the PH or decrease it. For most people the waters PH is about 7-8 so in that case you only really need PH down. Citric acid is perfect for this. It’s way cheaper than bottled PH down, you can get a kg of crystalline citric acid in most supermarkets for about 5€ and it‘ll last you a long time. Add a very small amount to your water AFTER you added your nutrients. Slowly increase the amount until your PH meter tells you that you’re in the correct range (6.2-6.5). With time you’ll get a feeling of how much to add. I can reliable add a pinch of citric acid to a liter of water and reach the desired PH range.

There are also nutrients that have „perfect PH“ built into them. That means when you add nutrients to your water it will automatically change the PH to an acceptable range. Personally I don’t like them but it’s a Choice that’s unto you. Either way a PH meter should be bought to check things from time to time at least.

If you mix your own soil (which is a bit more complex) you can use dolomite lime to increase the PH (rarely do you need to lower PH here) while also adding CalMag and Sulfur that’s contained in dolomite lime. This is often used by people who use acidic media like peat and vermiculite (that’s what I‘m using with some other additions).

Here‘s a very cheap PH meter that will need to be calibrated more frequently.

And here’s a higher quality PH meter that’s still somewhat budget friendly but more reliable.

Did that clear things up a bit? Any specific questions?