Tap Water and PH control

I am on my third week into my first grow and everything is going well but I am anticipating some issues.

First, I am transplanting into gallon pots (from Solo cups) very soon. Using distilled water will soon be not practical. Can I use tap water (city) if I let it set out for a day or is there something else I should do?

Second, I purchased the PH tester shown in the pic below. It was pretty inexpensive and I have no reason to believe it will not work but the more I read these forums the more I realize PH is very important. Is there a better product I should have?


1 Like

Here is the pic I forgot to attach.

1 Like

Yeah those things are pretty useless, specially the ph part of it. You’re going to need something like this, the tds meter is nice to have as well.


You can use tap water/municipal if it does not contain chloramine. Chlorine is ok, thats why you let it sit out for a day or two.
Some well water might be too hard (high ppm), or softened (salt), and therefore unusable.


If your muni water supply is high in solids like mine (550 ppm) then you may want to consider adding R/O to your grow.


Thanks for the reply. I saw that product and veteran growers seem to like it. Is that something that checks the soil or does it check the water before it goes into the soil?

1 Like

You use it to check and adjust the water/nute mix before giving it to the plant (6.5 being optimum for soil), can also use to test runoff water to see what’s going on with the soil inside the pot. You’ll also need some ph up and ph down to actually adjust the ph. The TDS meter can help with determining water quality of your tap and concentrations of your water/nute mix.


Thanks, I will get them.

I just put in an RO system (since everyone is hoarding distilled water) and I love it.


I agree with @Hellraiser ph is utmost importance. I purchase an inexpensive meter like that and was constantly calibrating the dang thing. I purchased one of these and it almost never comes out of calibration. Just another option. You can check your soil ph and ppm by doing a slurry test using ph meters like these.


If you can afford it an Apera PC60 is worth the investment. It measures both pH and EC / PPM.

Thanks everyone.