Why Not make PPM the Standard For Alkalinity ?

[Scrubber_steve]

Every other measurement is reported as ppm.
NH3/4
NO2
NO3
PO4
Calcium
Magnesium
Potassium
etc
Only alkalinity is reported in two other ways, meq/L & dKH.
130ppm to 200ppm. Easy

 

[Old Fritz]

Its confusing to me too. I once read a post and they wrote salinity was like 200, which I interpreted as 2.000. I was like "how are your fish even alive". Anyways it's kinda like metric and imperial system, its what you learn that you want to stick with even if one is more practical than the other. I accept that the metric system is far superior to the imperial system but I haven't made any effort to switch, because it isn't practical because everyone else here uses imperial. Same with when people come into my store, no one here uses ppm, and on occasion someone uses ppm and most times they just get a weird look.

 

[WillB]

Not a great answer for you but let’s get technical! Alkalinity itself doesn’t actually matter....

 

[WillB]

What matters is our concentration of bicarbonate ions.

 

[WillB]

The thing is though. That bicarbonate concentration is VERY hard to test for. But conveniently your alkalinity is like %90 (don’t quote me on that) due to your bicarbonate levels. So we use that as an easier way to test for it.

 

[WillB]

I think I learned that hear actually. Someone tell me if I’m wrong!

 

[Scrubber_steve]

Alkalinity is just a measurement of the level of bicarbonate & carbonate ions & the waters buffering capacity. The ratio of bicarb to carb ions is determined by pH. At 8.3 it it's totally bicarbonate. But it's the measuring system used to show its level I'm interested in here, & why we don't just all use the simplest one, ppm?

 

[JimWelsh]

Because meq/L is more meaningful and relevant.

 

[Scrubber_steve]

Because meq/L is more meaningful and relevant.

Maybe in pure chemistry applications, but for simply testing aquarium water parameters aligning all to ppm makes sense to me.

 

[JimWelsh]

Here you go. Knock yourself out. https://www.hamzasreef.com/Contents/Calculators/AlkConversion.php

 

[Scrubber_steve]

Here you go. Knock yourself out. https://www.hamzasreef.com/Contents/Calculators/AlkConversion.php

Yeh, I'm well aware of conversion calculators. The reason we need them, that's what this topic is about.

 

[CJS80]

Not sure, but I think it is because smaller numbers are simpler. With everything besides calcium and magnesium we shoot for low numbers. 8-12 Seems a simpler area to shoot for than 130-200.

 

[Scrubber_steve]

Here you go. Knock yourself out. https://www.hamzasreef.com/Contents/Calculators/AlkConversion.php

And that's a very good site too.

 

[Scrubber_steve]

Not sure, but I think it is because smaller numbers are simpler. With everything besides calcium and magnesium we shoot for low numbers. 8-12 Seems a simpler area to shoot for than 130-200.

But two others that are measured regularly, cal 420ppm & magnesium 1250ppm to 1350ppm

 

[Randy Holmes-Farley Verified Community Expert]

Maybe in pure chemistry applications, but for simply testing aquarium water parameters aligning all to ppm makes sense to me.

You realize that it is ppm calcium carbonate equivalents of a mix of different things in the water, of which neither carbonate nor calcium are the most common.

How is that simple? lol

IMO, it it just ridiculous. If everything were done properly it would all be in moles (like meq/l) and one could easily compare and understand relative values.

 

[hart24601]

Dang, both the reef chemistry heavyweights have spoken for meq/l I think I had better switch to using it!

Btw using Jim/Randy hydroxide 2 part for months now and it’s great so thank you.

Ok back to the thread now!

 

[Randy Holmes-Farley Verified Community Expert]

For those interested, I compare and discuss nearly all of the units of measure that reefers use here:

The Units of Measure of Reefkeeping by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-08/rhf/index.php

here's the mentioned entry for ppm calcium carbonate equivalents, which actually is used as a unit for alkalinity (Steve wants this) calcium, magnesium, and total hardness.

ppm calcium carbonate equivalents

ppm calcium carbonate (CaCO3) equivalents is an ambiguous unit used for a variety of measures by reef aquarists, including alkalinity, calcium, magnesium and total hardness. In the case of alkalinity and calcium, the unit refers to the amount (in ppm) of calcium carbonate that would have to dissolve into pure water to give the same calcium concentration or alkalinity (even if that would be impossible to accomplish). For calcium, 1000 ppm calcium carbonate equivalents equals 400 ppm calcium ion. For alkalinity, 100 ppm calcium carbonate equivalents equals 2 meq/L or 5.6 dKH. In the case of magnesium, the concentration refers to the amount of calcium carbonate that would have to dissolve to provide the same number of calcium ions as magnesium ions are present. For magnesium, 1000 ppm calcium carbonate equivalents equals 243 ppm magnesium ion. In the case of total hardness, the unit refers to the amount of calcium carbonate that would have to dissolve to provide the same number of calcium ions as the total of calcium and magnesium in solution. Using ppm calcium carbonate equivalents for magnesium and total hardness is poor practice as they are hard for most aquarists to understand, but they are used for historical reasons by certain testing companies (e.g., Hach, Figure 3). A calculator for converting between different alkalinity units is online here. A calculator for determining how much of different supplements to add to boost alkalinity, as well as calcium and magnesium, is online here.

 

[hart24601]

Whoa. Simple concept to confusing real quick.

 

[Scrubber_steve]

You realize that it is ppm calcium carbonate equivalents of a mix of different things in the water, of which neither carbonate nor calcium are the most common.

How is that simple? lol

IMO, it it just ridiculous.

If it is so ridiculous why do you use it as a legitimate measuring standard in your articles ?

Alkalinity
2.5-4 meq/L
7-11 dKH
125-200 ppm CaCO3 equivalents

Lets continue with the ridiculous where aquarium alkalinity levels are reported using three different measurements (hey, pop out the conversion calculator again )

Or, just pick one & stick with it.

 

[Mortie31]

Doesn’t the Hanna Alkalinity checker give a reading in ppm