Jandre2k3's Cardboard Flowerbox - 41 Week Perpetual SOG Part2 - Blue Planet Nutri

jandre2k3;1663661 said:

bigirishdoode;1663527 said:

well just the other day i jinxed myself by saying my cheapo ph pen as been so good to me for 2 yrs, now its acting wack, i got some odd readings so i tested it with my calibration fluid and its reading the 7.01 fluid at 8.6 and the 4.03 at 6.5 seems it needs adjustment .but my cali fluid is not new i had it stored in vitamin bottles i cleaned real well, what im wondering is ,is there a universal liquid product,common household item that has a known consistent ph i can triple check with before i bust out the tiny screwdriver and adjust it, my one and only hydro plant HBD is showing signs of ph problems so i need to fix it asap,, im gonna post this in a couple of you hydro wizard guys journals as well as mine, why i didnt think to get strips as a backup i dont know lol thanks in advance J

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White distilled vinegar is consistently the same pH about 5% to 8% acetic acid in water, with a pH of about 2.4


20 Mule Team Borax:

NIST standardized Calibration Fluids:
Why can borax be used to make a pH standard? All of the NIST pH calibration solutions (the pH 4.0, 7.0 and 10.0 calibration solutions that you might buy from a scientific supply house in North America) are made by mixing controlled quantities of an acid and conjugate base. So usually you would need to mix precise quantities of two different compounds to make a pH standard solution.

However, borax has a very special property. It can be regarded as an equimolar mixture of boric acid and borate ions (with the required counter-ions and water of hydration.) So, within its crystalline structure, it has both components required to make a pH standard solution. Better still, it carries both of them in precise quantities, because if it doesn’t, it really can’t be borax.

To make the textbook standard, you dissolve 3.8 grams of borax per liter of purified water. It turns out that 1/2 teaspoon of solid borax weighs just about two grams. It also turns out that the pH of borax solutions is only weakly dependent on the concentration of borax in the solution. So, we don’t need to be tremendously precise in our measurement of the borax to still produce a useful pH standard.

Because 1 quart = 946.4 milliliters (ml), if we use a pint of water and add a half teaspoon of borax to it, we should have a pH standard solution with 2 grams of borax per 473 ml or 4.3 grams of borax per liter. This is within about 10 percent of the standard borax pH calibration solution, and because of the weak dependence of pH on concentration, it is close enough for our purposes. So, you should be able to use everyday kitchen measuring equipment to make this solution.

Pure Borax in Distilled water pH is 9.18 at 25C or 77F

Now it does change a tiny bit as the temperature changes, so here's a table for that.

[SIZE=-1]Borax/Sodium Metaborate 3.80 grams Na2BO7 10H2O /liter)[/SIZE]
[SIZE=-1](Celsius)[/SIZE]	[SIZE=-1](Fahrenheit)[/SIZE]	[SIZE=-1]pH[/SIZE]
[SIZE=-1]0[/SIZE]	[SIZE=-1]32[/SIZE]	[SIZE=-1]9.464[/SIZE]
[SIZE=-1]5[/SIZE]	[SIZE=-1]41[/SIZE]	[SIZE=-1]9.395[/SIZE]
[SIZE=-1]10[/SIZE]	[SIZE=-1]50[/SIZE]	[SIZE=-1]9.332[/SIZE]
[SIZE=-1]15[/SIZE]	[SIZE=-1]59[/SIZE]	[SIZE=-1]9.276[/SIZE]
[SIZE=-1]16[/SIZE]	[SIZE=-1]60.8[/SIZE]	[SIZE=-1]9.266[/SIZE]
[SIZE=-1]17[/SIZE]	[SIZE=-1]62.6[/SIZE]	[SIZE=-1]9.256[/SIZE]
[SIZE=-1]18[/SIZE]	[SIZE=-1]64.4[/SIZE]	[SIZE=-1]9.245[/SIZE]
[SIZE=-1]19[/SIZE]	[SIZE=-1]66.2[/SIZE]	[SIZE=-1]9.235[/SIZE]
[SIZE=-1]20[/SIZE]	[SIZE=-1]68[/SIZE]	[SIZE=-1]9.225[/SIZE]
[SIZE=-1]21[/SIZE]	[SIZE=-1]69.8[/SIZE]	[SIZE=-1]9.216[/SIZE]
[SIZE=-1]22[/SIZE]	[SIZE=-1]71.6[/SIZE]	[SIZE=-1]9.207[/SIZE]
[SIZE=-1]23[/SIZE]	[SIZE=-1]73.4[/SIZE]	[SIZE=-1]9.198[/SIZE]
[SIZE=-1]24[/SIZE]	[SIZE=-1]75.2[/SIZE]	[SIZE=-1]9.192[/SIZE]
[SIZE=-1]25[/SIZE]	[SIZE=-1]77[/SIZE]	[SIZE=-1]9.180[/SIZE]
[SIZE=-1]26[/SIZE]	[SIZE=-1]78.8[/SIZE]	[SIZE=-1]9.172[/SIZE]
[SIZE=-1]27[/SIZE]	[SIZE=-1]80.6[/SIZE]	[SIZE=-1]9.167[/SIZE]
[SIZE=-1]28[/SIZE]	[SIZE=-1]82.4[/SIZE]	[SIZE=-1]9.155[/SIZE]
[SIZE=-1]29[/SIZE]	[SIZE=-1]84.2[/SIZE]	[SIZE=-1]9.147[/SIZE]
[SIZE=-1]30[/SIZE]	[SIZE=-1]86[/SIZE]	[SIZE=-1]9.139[/SIZE]
[SIZE=-1]35[/SIZE]	[SIZE=-1]95[/SIZE]	[SIZE=-1]9.081[/SIZE]
[SIZE=-1]40[/SIZE]	[SIZE=-1]104[/SIZE]	[SIZE=-1]9.068[/SIZE]

As for the 7.0 point... ummm... human blood ranges from 7.1 to 7.3, usually. Distilled water or RO water is SUPPOSED TO BE 7.0, but I have yet to actually see that.

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