pH testing questions per tap and filtered H2O

Our water has a high pH. I got some pH down for hydroponics yesterday and have a digital pH meter ordered that should be here next week. I used the pH strips that we use for the hot tub to test the water from the sink (raw well water). I knew it would be high, so tested only water after it ran through a Brita Zero pitcher. So TDS is 004 right now and the pH color post test was yellow. I have never seen yellow so did trial with the filtered water and the pH down. Still tested yellow. So, noticed that the pH color of sink water is in the high alkaline range, which I knew it would be. But testing the filtered water it is yellow. I have no idea now which way to go on getting the pH right.

FWIW, I have an AutoPot system coming this week. My seedlings are two weeks old, and growing in the grow tent. They are getting filtered sink water and so far look really good. I just need to figure out this pH thing before they transition to the AutoPot system.

Top strip is sink water and bottom strip is filtered water. Second tab from rightimage

With that low of a tds, ph’ing wont be necessary. You’ll only need to adjust ph when adding nutrients to the water. I’d suggest a digital PH pen as they’re far more accurate than the test strips.

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Thank you. I ordered one yesterday but it won’t be here until next week.

Yes gotta have a pen, but if I could get a strip that checked ph, calcium and ppm levels like that strip that would be awesome.

I’m colorblind so they don’t help me in the slightest, lol


You can get them at a place that sell supplies for hot tubs and pools.

I priced a digital pH meter that read PPM, TDS, and chlorine as I thought it would great for hot tub testing, too. It was $895. Will just keep buying the strips so I can gauge chlorine.

It just puzzles me as to why filtered water would turn the pH part yellow.

Yes I got plenty of those strips for my pool, but it would cool if they had one to the check the specific needs for growers. Better call the patent office million dollar idea lol.

Sorry to laugh but that is funny. That is kinda like when I ask my husband, who is nearly totally deaf “did you hear that?” I get 'the look" :rofl:


Because that low of a tds won’t support a true PH. The water will become the ph of whatever is poured into it or whatever it is poured into.

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Oh hey I hear ya there! was having a conversation with our 32 year old son yesterday that we need to come up with the next best thing in cannabis. he said, “breeding a cup winning strain?” No dude! make some sort of product that goes with cannabis. Look at those guys who invented PAX and all the ancillary stuff. That is where you need to look. Well…mabye we can figure this one out. :smiley:

BTW, NOTHING has bonded us to our son more than cannabis. He is a Marine wounded warrior and we would rarely hear from him or even know where he was. He was a budtender in Washington. Helped someone harvest one year in Humbolt county. Now that he knows I am growing I hear from him almost daily and we are bouncing ideas off of each other. It has been a great connecting point for us.


This is what I got. I debated on spending more or less. This one seemed kinda mid point for me. I got a TDS meter with the Brita Zero pitcher. ($20 so kinda neat it came with the pitcher)


That’ll serve you well. The cheaper ph meter require more frequent calibrating. Annoying levels of calibrating.