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General Hydroponics pH 7.0 237mL

Price: $15.00 Loading Data
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General Hydroponics pH 7.0 Calibration Solution is used to adjust your pH meter using the highest quality reference solutions, allowing growers to calibrate many popular brands of PH, EC and TDS meters (NaCl scale or the 442 scale). Easy to use, just dip your electrode into a small amount of the buffer and adjust the meter to read 7.0. Do not reuse solution. Suitable for all makes and models of pH pens and meters. Each batch is carefully checked by General Hydroponics technicians to ensure that it is precisely calibrated and yields reliable readings every time they are used.

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Product details
Shipping Weight: 0.45 Kg
SKU: 2006
Date first available: July 06 2017
Average customer review: 4.5 out of 5 stars 796 customer reviews
Bestsellers Rank: #9 in Measuring Device
Customer reviews

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Tommy Blaze


Verified Purchase

November 10, 2014

This makes me to be able to quickly, and easily calibrate my PH meter/pen whenever I go to use it! Especially since they recommend storing the open end of the pen when, "Off", in just enough solution to make sure the pen/meter's test diode doesn't get unwanted build up, damaged or broken a lot more easily! I highly recommend this solution if you're required to take accurate pH readings and use a device , meter, or a pen that periodically needs to be calibrated for accurate readings! The subject matter being tested can make regular calibrations critical due for the need of survival, like when dealing with plants/horticulture, fish aquariums,etc, or when it may become a problem!



Verified Purchase

July 13, 2015

Oddly, this and the packets do not seem to show up the same. I tried mixing the packet included in the PH Pen, and this, But the 6.84 and this 7.0 solution do not match. I have used this on its own since. Seems to work well.

I've found it best to get a dropper or pipette and transfer this into a cleaned out tic tac container to be able to use without contaminating the solution bottle. Storage is simple and it has not lost any points for me over the couple months I've had it.

J. Daley


Verified Purchase

June 06, 2012

Although I know better, I wish you could dump your test solution back into the bottle after you were done. I've used this product for a couple of years and I never trust the PH Tester. That's why I calibrate my tester every time and when you're on a 3 day watering cycle you go through quite a bit of calibration solution. This is the only way to make sure your water is at the right PH for whatever prize plants you may be gardening. Totally necessary (Recommended).



Verified Purchase

October 29, 2012

I use this to calibrate my digital pH pen every time I water or feed plants and am very pleased. I only use a very small amount (even though the instructions say to use a good amount of it), and instructions are printed on the bottle. It's not the biggest bottle, but so far has lasted me a few months and now I am planning on grabbing a large bottle once I've used all of this. Works consistently every time and would recommend for anybody that uses a pH tester.



Verified Purchase

Turns out my meters off by 0.1ph who would do guessed ?

October 05, 2018

So worth the 5$ just to find out the meter was brokenness / starting to go and needed new one before I lost a crop to the stupid thing so for 5$ 5/5! Heck 6/5 lol saved my bum thank you great product it

Essensially you just take a shot glass and water fill and put this in and see if it’s 7.0 if it says not you got a problem by that much ph your meter is off by... perhaps I used it wrong but I wasn’t suspicious of that meet any way lol!

barry n


Verified Purchase

March 19, 2013

I stuck the brand new pH meter I also ordered into a cup of this stuff, and twisted the calibration screw all the way to the limit. The closest I could get was 6.6. Now, this was for a 5th grade science experiment, so we were of the "eh, close enough" mindset. Nevertheless, either something was up with the solution or the meter. OR, also possible, there was some residual dishwasher chemical in the container that simply dropped the pH. Dunno.

Rick S.


Verified Purchase

July 31, 2012

So I read other reviews that talked about their package being wet and the bottle empty. After seeing how my order come, I can set your minds at ease. To start with there is a seal under the cap, and if that was not enough they secured the cap to the bottle with tape. So that tells me that they read the reviews, and took steps to try to prevent it from happening again.

I give the Co. two thumbs up.

M & L Hurton Fam ❤️


Verified Purchase

May 02, 2013

this stuff is great for calibrating your ph meter and keeping it as accurate as possible. I use it once a month or so.. you pour some in a glass... put the meter in it and let it read... then push the "calibrate" button on the meter.. the ph solution is 7 so when you push the "calibrate" button it tells the meter whenever you read this amount of ph in water it is a 7.. takes 30 seconds, nice and easy



Verified Purchase

June 20, 2014

I have been using general hydro calibration solution for a few years now and it's never let me down. Always comes in calibrated at the right pH and lasts awhile. The only strange thing I have noticed is that if it sits for a long time there are little bits of solution that start to float around in the product. Doesn't seem to affect the pH, just more of an aesthetic thing. Great product nonetheless.

Derek. E


Verified Purchase

January 18, 2014

Everything General Hydroponics makes is good. I got this to use on a new Ph meter I bought. Which was ideal because it seems to need to be slightly adjusted every time I use it. This bottle will last you for years because you can reuse solution. Another reason this stuff is good and accurate is because I don't have to have a certain Ph water mixed with the powder solutions. This stuff works well!

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