Test water PH, or not?

Hey everyone,

I currently have a NYC Diesel Auto that’s two weeks old in a 5 gal bucket filled with very neutral soil. Completely unammended Pro-Mix BX.

Our next watering is coming up and I am not sure if I should be PH balancing my water or not. I haven’t fed her anything yet, but when I do, I plan on feeding her organic dry fertilizers through top dressing.

I heard PH up and Down can kill off the microbial activity that I am trying to build in my soil, but my tap water also is testing out at 8.0 PH after dechlorinization

So my question is: If I haven’t fed her anything yet is it safe to PH down my water or is there another solution I’m missing?

I would say ph your water to between 5.8 & 6.5 would be ideal, imho.

PH should be between 5.8- 6.8. Anything higher than 7 is too high. I use ph up and down on my autos when necessary and have not noticed any stress on the girls

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Soil has an AMAZING ability to adjust the ph all by itself. That doesn’t mean you can go in and feed with a ph on the scale that would injure or stress the plant. Are you objectionable to bottled water? Even a cheap gallon of distilled or filtered water is less than a buck. I buy 5 gal bottles and get RO water for .29 a gallon…my TDS (which is just as or even more important than Ph) is less than 1…My ph is around 6.2…When you start adding LIQUID nutrients or additives or amendments, you will change the ph and TDS. Top dressing is a good way to lessen your need to adjust but unless you are using living soil, and you are not, there are necessities you should be adding that affect all of this.
Molasses - will lower ph of soil over time…but is highly recommended at 1 teaspoon per gal of water. Kelp will also assist in CREATING THAT SUBSTRATE that has the micro-biological ability to make you plant grow better. Cal/Mag will be a requirement becasue your soil has NO CALCIUM…The calcium, mag and sul are NEEDED!
Ph up/down, when used properly, will not DESTROY your substrate…just do not use both. If you overdo it, going up or down, do not adjust the other way. Take time, use it drop by drop, aerate, test, aerate and test again…Aeration alone will change the ph of H20…
TDS - the solids in tap water register as salts and count towards nutrition. When you mix in your additives, the TDS values will change as will the ph levels
If your water is 8, you want to lower it to at least 6.2-6.5…Molasses will lower it even more. Kelp will help the roots and add the beneficial bacteria to the substrate, as will the molasses and Cal/Mag. If you do not have cal/mag, either get it or look at @Kronic home made formula…I make my own using eggshells and epson salts…


To add to what @Mrb53004 has said so well. Your tap water probably has a crazy amount of calcium/magnesium/who knows what in what amounts. At least cut your tap with store bought. That alone will bring down the ph and hardness.

You said your in straight promix, so yes definitely ph your water. While it has already been pretty well set to stay at 6.2ish, 8.0 will be an issue. My current grow is just promix, top feed hydro nutes, and it’s always PH to 6.2. 8.0 will cause some nutrients to be locked out.

You can get a cheap PH pen off Amazon, also can use the dropper kit for aquariums from walmart. Regardless of how you need to PH correct your water.

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