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by General Hydroponics

Price: $24.99 Loading Data
In stock

Achieve optimal plant growth with precise pH level monitoring

Ensure a healthy and thriving garden through accurate pH testing

Avoid nutrient lockout and maximize nutrient absorption with perfect pH levels

Enhance your hydroponic system's efficiency with reliable pH measurement

Experience the ultimate ease in maintaining optimal pH balance for your plants

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Discover the key to unlocking your plants' full potential with our exceptional pH Test Indicator solution. Designed to cater to the needs of both beginners and experienced gardeners, this 8-ounce bottle of test indicator is perfect for monitoring and maintaining the ideal pH levels of your hydroponic system, ensuring optimal plant growth and health.
To use, simply fill a test vial with your nutrient solution and add a few drops of the test indicator. Within seconds, the solution will change color, allowing you to compare it to the included color chart and determine the pH level. This easy-to-use test indicator takes the guesswork out of pH management and helps you avoid nutrient lockout, ensuring your plants receive the proper nutrients they need to thrive. 
Our pH Test Indicator is compatible with all types of hydroponic systems, including nutrient film technique (NFT), aeroponics, deepwater culture (DWC), and more. It is suitable for indoor and outdoor gardens, as well as soil-based growing mediums. With its affordable price and reliable results, this test indicator is a must-have tool for any serious gardener looking to optimize their plants' growth and overall health.
Take control of your garden's nutrient absorption and pH balance today by investing in our high-quality pH Test Indicator solution. Your plants will thank you for it!

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Product details
Product Dimension: 20.32 x 20.32 x 15.24 cm
Shipping Weight: 1.25 Kg
SKU: 1423

Manufacturer: General Hydroponics

Date first available: March 16 2016
Average customer review: 4.7 out of 5 stars 1208 customer reviews
Bestsellers Rank: #1 in Measuring Device
Customer reviews

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robb w.


Verified Purchase

August 18, 2015

Came quickly enough, didn't realize I'd run outta this stuff until the day my back-up pH meter crapped out on me less than a week after my good one died lol, so yea.... Desperate times. And although I ordered my new meter w the same transaction as this litmus solution, it's not expected for another week @ least while I've had my big bottle of litmus liquid over a week.
Another thing, u may wanna get u a bottle of this as backup even if u have a good pH meter, they all crap out/require calibration/ batteries die & it always seems to happen at critical times. Having this little cheap plan b can save u a lot if hassle and heartache, the small bottle I'd got of it when I ordered a pH adjuster kit n my early days is what clued me in to my meters being outta wack, probably saved a lot of issues. It's always good to have a back up like this, not really prone to the problems/ limitations of more "advanced" data collection devices

Joe S.


Verified Purchase

December 25, 2022

I ordered this PH test kit because it was rated highly and was inexpensive for the amount in the bottle. I expected a decent test color chart, not the wide ranging few colored stripes on the bottle. The stripes jump from 5.0 to 6.0 then 6.5 to 7.0 then to 8.0 and finally 8.5
I'm looking at a PH level chart for hydroponic growing and several vegetables are in the 5.0 - 5.5 range and nothing is over 7.0, so how about giving us a 5.5 stripe and a 7.5 one and doing away with the 8.0 and 8.5 stripes? Or, assuming there are things that require that range how about making them a little more narrow and fitting all the .5's in ?? Seems pretty cheap and dumb to me to leave them out.

I am disappointed and won't buy again as I don't need to be scratching my head and squinting at the strips trying to make a decision, is it x or y?



Verified Purchase

March 14, 2019

pH Meters are cool. They make testing your solution super easy and are a real time saver. Only problem is they are quite expensive overall, and are prone to drifting readings as well as general failure, no matter how well you maintain and calibrate them. It's gotten to the point that the only real issues I have with pH and in turn my plants, is when a pH meter decides is isn't going to tell the truth anymore and I see the deficiencies because of it. Tired of playing games and wasting money on them, only to be forced to double check the meter's results with drops anyway... So I just use these drops and no more issues.



Verified Purchase

May 21, 2017

Works perfectly. Cost only a couple of bucks more than a 1-ounce dropper bottle of the stuff. Use a plastic pipette to measure out drops directly from this large bottle or refill a smaller dropper bottle*.

*Be warned that attempting to pour out of the completely FULL bottle into another container is tricky and can make a mess - this stuff will semi-permanently stain many types of surfaces, like a porcelain sink. A rag dampened with 50/50 bleach and laid over the stain will usually remove it, but that's not assured and could damage the stained surface (but not a problem with porcelain).



Verified Purchase

June 15, 2019

I use this to test the ph of my drinking water and also the ph of the water I use to grow hydroponics. I also have a digital ph meter (the button batteries just died), so that's why I'm getting this again. Just remember, the water from a faucet or bottled water always seems to be too acidic (Usually around 6.0ph-6.8ph), and the ph scale goes from 0-14, so 7 is neutral and 6.5ph is too acidic for my drinking water because our blood ph is around 7.35-7.45ph, so I always alkalize my water and this is an accurate product to measure with.... most likely I will buy again when I run out



Verified Purchase

January 12, 2015

This is simple to use and accurate. But the 6.5 color swatch on the bottle does not exactly match the actual color of the water in that range (a printing problem?). It looks more golden. It is not orange like the 5.0 swatch but it could be haphazardly misinterpreted as an orange 5.0 match. But when adding four drops of the test indicator to the vial, some of the color is dark green before the indicator is mixed with the water — and that's how I know it's in the 6.5 range. That's my experience, what's yours?



Verified Purchase

May 06, 2015

Just A giant version of the smaller bottles that come with the testing kit or ph up/down kit. It comes out to be 8 of those smaller, dropper style bottles. This larger 8oz version does not have any dropper on it.

It's basically a refill supply. Make sure to keep it in the dark cooler places for storage. Also, when filing your smaller bottle(s), buy a plastic eye dropper or pipette, and just squirt the solution in.. do NOT try to pour it... it will dribble and spill. You were fore warned heh.

Ryan and Lisa Dake


Verified Purchase

March 27, 2022

I've use this brand for a loooong time now and hasn't ever disappointed me. It's accurate and easy to use. This is a refill bottle for the smaller one they sell that comes with the vial. I'd highly recommend it. My hydroponic vegetables grow great using this to keep my ph in check. The only downside I can see is if you're color blind this is not a good product for you. I hope this review helps someone out and if so hit helped I like to see if my review helps someone. Have a great day!!!!



Verified Purchase

January 28, 2016

This is the best way to check the PH of your hydroponics system, or your swimming pool or tap water or about anything really, and this bottle is HUGE compared to the other test kits. Refilled my smaller bottles with this, should be able to refill them 10 times I bet. If you check your PH a lot this is the way to go. keep my DWC hydro at 6.0. Tap water is usally 7 to 8. baking soda will raise PH, Vinager will lower PH. 1 to 2 drops of vinager per gallon drops it 1 point. about perfect.



Verified Purchase

August 20, 2021

I have tested it against a pen a couple times and find it close or right on all the time, what I mean by close is the color is hard to read from 6.0 to 6.5 the sweet spot I’m looking for, I like it because I don’t have to keep calibrating a pen great for a quick test to see where you at, there is a picture on the net with the different colors in the vial that really helps and I hold the vial against e white sheet of paper have already purchased it again definitely would recommend

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