You can buy a ppm and Ph pen together for extremely cheap. Those tools are the most important for any grower. Sure I don't use either anymore but I wouldn't play a guessing game with my plants initially. Neglect of either can quickly lead to lockout, dead plants, and wasted time and money. All of which could be prevented by a 20 dollar investment.
Just my 2 pennies. Best wishes.
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Just my 2 pennies. Best wishes.
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