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GH pH Down Liquid 4 Litres

by General Hydroponics

Price: $49.99 Loading Data
In stock

Unlock the power of healthy plants with GH pH Down Liquid

Achieve optimal pH balance with a simple and easy solution

Restore and maintain the health of your plants with GH pH Down Liquid

Experience a maximum growth potential with GH pH Down Liquid

Keep your plants thriving with GH pH Down Liquid

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General Hydroponics pH Down Liquid is an easy to use solution designed to lower the pH of nutrient solutions. This liquid is ideal for use with all hydroponic, aeroponic, and soil-less growing mediums. By adjusting the pH of the nutrient solution, you can ensure your plants are getting the desired amount of nutrients, resulting in maximum growth potential. GH pH Down Liquid is easy to use and can help create an ideal environment for your plants to thrive. The pH Down Liquid is designed to be used with all hydroponic, aeroponic, and soil-less gardening systems. It is formulated to be used with any type of nutrient solution, including General Hydroponics nutrient solutions. It helps to maintain the pH at the ideal level for maximum nutrient absorption. By having the proper pH level, your plants will be able to absorb more of the available nutrients, resulting in a more vigorous growth.

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Product details
Product Dimension: 33.02 x 22.86 x 17.78 cm
Shipping Weight: 5.44 Kg
SKU: 2212

Manufacturer: General Hydroponics

Date first available: August 30 2018
Average customer review: 4.7 out of 5 stars 2857 customer reviews
Bestsellers Rank: #19 in General Hydroponics

Christopher Pinto


Verified Purchase

June 25, 2020

Great large size of ph down! Needed this bad! Holland Industry is the best!



Verified Purchase

November 16, 2015

Before purchasing this brand of pH Down I did some research as to figure out what type would be most worth the money, and I learned some what I feel to be very important things. Another brand name of pH Down is 5-TIMES WEAKER than he General Hydroponics brand, and while they do not state what the percentage of dilution is, I have learned that it is "Food Grade". I also stumbled across some "Pharmaceutical Grade" and wasn't sure which one was more worth the money... But if you look at all your hydroponic equipment everything is made to "Food Grade" standards, so why shouldn't your pH Down also be? When I did more research I also learned that this is the number #1 most talked about brand everywhere I looked and most recommended by other gardeners all over the internet, so that helped influence my choice towards this brand.

As far as the size of the bottle and the amount you need... This bottle should last me a couple of years, but I just bought some much smaller bottles and will ration it out into smaller bottles to avoid contaminating the 1-gallon bottle, and from the smaller bottle I can use a pipette to add the drips of pH Down to my water to bring the pH Down. Overall I am very happy with the 1-gallon size bottle and will either continue to buy it in this size or in the dry powder form when it becomes available again at the end of 2015, as I am told they had a manufacturing issue with it and won't have it back up being sold again until then.



Verified Purchase

April 04, 2020

It works you need a ph meter, it depends on the nutrients you use. And yes every couple days you will have to adjust it... why because your plants are eating food drinking water and as your nutrients level goes down your pH level will start to raise. Rule of thumb when you need to use pH Up. It means it's time to change your tank rule of thumb no more than two weeks and you should be changing your nutrients for healthy plants. It works as designed the few people that say they wish it lasted longer while your plants eating food that's why your pH level changed slept a good thing. With what I'm using I have a 50 gallon tank. After I mix my nutrients roughly 4 tablespoons is all I need in about every 2 or 3 Days 1 tbsp to keep my pH level on balance. Very important to keep your pH if it's too low you've going to deprive your plants and if it's too high you're going to deprive your plants of much-needed nutrients your lock out there food. Can you buy a cheaper yes of course she can like anyting

Matthew Cole


Verified Purchase

January 29, 2022

I purchase 1 gal of pH Down and 1 gal pH Up. The two arrived together in a plastic bag in the same box. Half the box was completed saturated. Turns out almost half the UP had leaked out. Some was still in the bag but enough had escaped to saturate the box to the point of crumbing. The bottle had been mashed in but the seal on the lid appeared fine, so I assume there must have been a tiny puncture either in the lid or the bottle itself. I have used the product before and it works great. However, I was really disappointed in the shipping damage.

Backwoods Bulldog


Verified Purchase

November 11, 2022

This to me was a no brainer. 128oz for roughly 2x the price of 8oz. It may or may not make sense for everyone as this stuff lasts forever. A little goes a very long way. But I grow quite a bit and use enough that it is justified to buy this in a gallon size at this price. Maybe split the cost with a friend if you really don't need that much. As far as the actual product it works outstanding at adjusting the ph and 3 or 4 ml will drop 4 gallons on my water from a 6.9ph to a low 6ph. It really goes far.

Kimber Summers


Verified Purchase

November 10, 2021

I use this in my indoor hydroponics set up and the large size is great as my water always needs adjusted down. This gallon has lasted me about 6 months, but i noticed after about 2 months, i was putting in more product to adjust the pH the same amount. Nothing has changed in terms of the amount of water or size of container im using, so i cant imagine what would be causing this other than the deterioration of the product over time



Verified Purchase

August 22, 2023

Love this product, i have been using for the last 3 months. From tap my water is floating around 250ppm and 7.0 pH. This product alone without any other ph up has been wonderful to use. I havent dosed enough to float away from 5.0 pH, growing in coco cior. If this does happen, silicon usually does the trick to raise while adding to the ppms. Just be mindful. This is an awesome product, would def buy again!



Verified Purchase

February 05, 2021

As usual PH Down does not disappoint. We've used this brand for years but if I can remember right this is the first time we have bought it by the gallon. It arrived safe and secure and it's doing it's job so you can't really ask for better. Perfect for all of your hydro projects!

*I take reviews very seriously and If this review helped you let me know by hitting the Helpful button, Thanks!*



Verified Purchase

June 05, 2023

I use this product in my hydroponic greenhouse, especially with NFT strawberry pH control. Strawberries are very sensitive to pH changes. I have a 15 gallon reservoir and measure daily to keep it between 5.5 and 6.0. I added 10ml today to drop the pH from 6.25 back to 5.95. I have to do this about twice a week. At this rate one gallon of pH Down will probably last me the rest of my life.



Verified Purchase

June 14, 2021

This is Phosphoric Acid NOT Citric acid! ...I was not able to find that until it arrived and I turned it around and read the label ingredients! ...I recommend they make it better known in big bold text in the description! ...so you can know right away before you buy! ...I was so worried I was gonna end up with more citric acid which I already had! ...price is a little high!

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