Can You Use Vinegar To Lower PH In Hydroponics?

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By Alex Harris

If you’re looking for ways to lower PH levels in your hydroponic system, then yes vinegar can actually help.

It will break down excess alkalinity over time so it’s not as likely that you’ll need pH up solutions when using this method. That said, there are some things to keep in mind.

Vinegar is very acidic, so too much can actually raise pH instead of lowering it depending on how you use it.

It’s best used at a low concentration and make sure that your system has enough ventilation when you’re using this solution.

Also Read: Best PH Meter For Hydroponics

How much vinegar is needed to lower pH in hydroponics?

One cup of vinegar solution is sufficient to lower pH by 0.35-0.45, which means you will need about two cups of vinegar for every ten gallons in your hydroponic system if you want to drop the level by half a point.

Or if you’re working with a smaller hydroponics system, then 2 tablespoons per gallon.

Will apple cider vinegar lower pH in hydroponics?

No. The use of apple cider vinegar will only serve to increase your acidity and it is unlikely that you can achieve a significant decrease in the PH value with this method.

Having said that, if you mix the ACV with other ingredients such as Epsom salt (magnesium sulfate), then it may be possible to lower the PH value.

Epsom salt is soluble in water and will act as a nutrient for your hydroponic plants, improving their growth capacity by providing them with magnesium which also helps increase photosynthetic rates.

Stick to distilled white vinegar which you can buy from most local food stores.

What can I use to lower pH in hydroponics instead of vinegar?

If you don’t want to use vinegar, there are some other methods to lower pH in your hydroponic water like: calcium hydroxide, potassium carbonate or phosphoric acid, but vinegar is recommended as it’s natural.

Remember, whatever you put into your water, your plant roots will soak up, so the more natural nutrients you add to your water, the more organic your plants will be.

If you have a larger hydroponic system like an ebb and flow, DWC or NFT etc. Then vinegar is not as effective as other methods to lower pH because it’s difficult for the acetic acid in the vinegar to make its way around your entire water supply.

Quick note: Phosphoric acid is not as good for the environment, so be mindful of how much you’re using and where it goes! That’s why a lot of hydro growers use calcium hydroxide which will also increase alkalinity at first before bringing down your pH level over time to provide optimal growing conditions.

I’ve lowered it too much, how do I increase my pH?

Easy, just use baking soda to raise it back up to normal levels.

ph levels too low

Each time you add sodium bicarbonate, use a pH meter to check pH and control your levels to ensure nutrient uptake.

If you find that it’s not working, try adding more water to dilute out the baking soda so it doesn’t become too saturated with alkaline particles.

As long as you don’t go overboard by using too much vinegar or baking soda, this should be a safe process for both hydroponics and soil pH.

Why do I need a PPM meter?

A PPM meter measures the amount of nutrients available for your plants to absorb. The more concentrated nutrients are, the healthier and faster your plants will grow.

It’s an essential tool because it allows you to monitor the nutrient strength in order to determine when it is time add extra or less water/nutrients as needed.

Is your PPM count over 400?

If your parts per million count is over 400, then you really should flush out your hydroponics system and start fresh.

The reason being is because you run the risk of salt burn or buildup, which can damage your system entirely. Obviously, that can be costly, so keep an eye on your salts!

Why does the pH level matter in hydroponics?

The pH level is important because it can affect how well your plants absorb nutrients.

Vinegar only lowers the pH of water, not soil, so you must use vinegar to adjust PH levels in hydroponics systems that rely on nutrient-rich water instead of dirt like NFT and DWC systems. It’s safe for your plants and actually effective.

If your system is too basic or has a high pH level of eight or more, it can lock out the good nutrients that you are giving to your plants—and they will die. It’s important to keep an eye on this number in order to prevent nutrient lockout in your hydroponic garden.

Conclusion: What to do next

Grab the following tools and then get to work, drop pH until they are at the right amount. It’s important to note that pH adjustment takes some trial and error.

  • A bucket – Big enough to hold your water and test things out.
  • pH tester/meter – Used to check your levels, ideal if it has a probe.
  • PPM meter – Also know as a TDS meter. It’s used to determine the total amount of dissolved solids in parts per million. In general, when your PPM are lower, it’s easier to control your pH.
  • Distilled white vinegar – Use to bring pH down gradually. Make sure you’re using the meters above to check each time you add some.
  • Baking soda/sodium bicarbonate – Reduced your pH too much? No worries. Just add some baking soda until you reach stable pH levels.