Hard water and high pH


New Member
I just moved to a new place and I'm trying to do some 5 gal DWC buckets. It was working out good at the old place where I had clean water but this new place has really hard water. From what I could search on here, it looks like hard water usually has high pH. At the old place I would use a few sprinkles of GH down and it was perfect. I've got a new pH down and it seems like a whole tsp still isn't enough. Are different dry pH downs that different or are all the minerals in the water stopping it from working as efficiently?

Yesterday, I made 2x5 gal buckets with 1tsp maxi grow and 1/2 tsp TNB down (derived from hydroxy propane tricarboxylic acid). Today one bucket is at 8.8 and the other, I gave it another 1/2 tsp of down it's at 7.3 and the tap is around 8.

Should I switch to liquid nutes? The dry stuff was easy to use and cheap. Worked good when my water was at 40 ppm but is it having trouble saturating in this harder water?


Well-Known Member
My tap water is 7.4 ish. I use Dyna-Gro liquid nutes. The full line Pro-tekt, Grow or Bloom, and Mag-Pro. At about 1/3 strength I add 1ml of general hydroponics PH down per gallon. Spot on PH at about 5.6-5.8. Your milage may vary. When I go to 1/2 strength I don't even need PH down. Great stuff. something to think about.

The Dyna-Gro Pro-Tekt actually works fantastic as a PH buffer.
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Well-Known Member
The strongest ph down on the market is advanced nutrients ph down its 55% phosphoric acid. But there is other ways of balancing the ph. You can use a device called Toraus hydro they make this device that you toss in the water and it balances the ph automatically and keep its drifting in the range for what hydro plants require but for 5gal buckets it wouldn’t be ideal. I would check out the advanced PH down


Well-Known Member
My tap water is around 8,5 or 9 pH, ppm around 450. It's a limescale factory over here..
I use citric acid to lower pH, about a finger-pinch of citric acid is enough for a 2-gallon bucket of water lowering it to 6,5 pH
But i grow in soil with liquid nutes and i use the water right away. Letting the water sit for a day or bubbling it with air will raise the pH


Well-Known Member
You should see what the EC is, then add some citric acid and take another EC reading. The EC may be a lot lower. If the EC is in a acceptable range then drop pH to 5.8 and check the pH the next day. If it rises up out of range i would go down to 5.5 and check next day. There will be some pH where the alkalinity is neutralized and it will not jump up so quick. Because of N form it will go up some. Dyno gro and Jacks Tap have a little more NH4 which is probably better way to go with your water.