pH Down verses White vinegar

I have been using pH-down to lower my water from 9.2 to 6.5 to water my Bonsai. Will white vinegar be as useful as pH-down ?

Bill D


Hydro-ponic pH down or swimming pool/ hot tub pH down?

The one is safe for plants, not necessarily the other.

The Hydroponic one is just fine. Been using it for ages. I tried to use citric acid, I keep a 45 gallon drum of water and adjust the Ph of the whole amount. When I used citric acid it went cloudy and smelt awful within two days. I have had no problems with ph down bought from a Hydropinc shop. Make sure to use a good quality Ph meter. One other thing, if the TDS is high the Ph will slowly creep back up over a week or so. Not a problem if you have a lot of trees. :grinning::grinning::grinning:. I wouldn’t go down the route of adjusting small amounts everyday. I’m seriously thinking of investing in a Reverse ósmosis unit, again that comes with you having to do some work with the chemistry after it’s made. Happy to help further if you need it. Ryan I believe has more information on the vinegar system.

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I concur with @Nicknjh23. I personally have used both pH Down and white vinegar to acidify tap water. Currently, I use vinegar because it is easily accessible and is very cheap. Its aroumd $3 a bottle and last a full growing season. I mix a teaspoon of vinegar per gallon of water and to adjust the pH of my water from 7.5-7.8 to 6.2-6.5. I’ve also used a hose end sprayer as well, it required some math to get the concentration I desired with the dial adjustment takes it worked well. Heres a link to a small aprayer thats around $10 on Amazon.

Ortho Dial N Spray Multi-Use Hose-End Sprayer

An RO system would be nice but for now I’ll just keep using diluted vinegar for acidification. I also have found that monthly application of vinegar solution has been optimal for maintaining the desired ph for most of my trees. I also use zeolite for its buffering capacity and high CEC, turface for acidification its pH is ~ 5.5 ( Ryan hates turface) but I have no problems from using it. In addition, consider adding pine bark or fir bark at about 10-20% of total mix volume. They also have relatively high CEC and water retention capacity, Akadama is great but I’ve not seen the 3-5mm size that I want in about 6-8 months.

Basically, watering and substrate solutions can be found and dont have to be expensive or exotic.

Good luck with your bonsai!



I believe the brand pH-down for horticulture is usually food grade phosphoric acid, which can have some implications for your fertilizing program if you are using a lot of it. A pH of 9.2 is very alkaline and could point to very high total alkalinity. Which would make your water have a high buffering capacity and result in you needing to use a lot of vinegar to affect a change. If you are part of a water district, let’s take a look at their water quality report and we can really dial in your potential issues. The reports should be online.

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