jarrod0987
Aquarium Advice FINatic
- Joined
- Jul 12, 2005
- Messages
- 512
Myself and another member were discussing Calcium in the planted tank today. How important but unknown it is to many planted tank keepers. Calcium deficiency has been associated with misshapen leaves and sometimes wrinkly leaves which can also be cause by other problems.
Most hobbyists use the GH test kit from API. They are unaware that is is a test that looks at Calcium and Magnesium combined. They are also unaware of the fact it does not tell them how much of each one. You could have 2 tanks with the same GH and wonder if you had any magnesium at all or any calcium at all. Usually, in FW, you have more calcium then magnesium. Both are important to plants.
We were wondering how close the GH test kit even is. Is it even worth getting.
Let's find out
I paid out the 51$ for my Hardness, Total Calcium & Magnesium, DRT kit from LaMotte.
(Code 4824-DR-LT-01)
I also have a combination GH KH test kit from API for around 7$.
Both kits are within there expiration and less then a year old.
For reference: 1 German Degree of Hardness = 17.857 ppm.
Calculator I use is here:
SaltyZoo's Alkalinity Reading Conversion (meq/l / dKH / ppm CaCO3) Utility
So let's get testing!
My tap water has a dGH of 8 as per the procedure in the API booklet. Really, it does a partial color change at 7 so I will call it 7.5 dGH.
The LaMotte uses the more accurate mg/l (ppm) measurement. So we will convert.
What LaMotte calls Total Hardness is the same as API's GH.
The result is 106 ppm which is 5.936 dGH. That is an error of 1.56 dGH or 27.93 ppm.
I did each test twice and I got exactly the same results both times so the repeatably is not an issue.
Some people would report this as a 20.8% error. That is actually pretty big as errors go. However, in a planted tank you can always just add a little more then you need and be alright. You can also watch the plants for signs of calcium deficiency which shows up as misshapen new leaves. Also, plants can die very fast if Calcium is depleted.
Just for kicks I decided to also break it down further into Calcium and Magnesium.
Calcium was 62 ppm (3.472 Degrees of Hardness)
Magnesium was (By Subtraction) 44 ppm (2.464 Degrees of Hardness)
The ratio should be 3 to 1. I am closer to 2-1. I don't believe it is a big deal as long as I have enough of both.
My conclusion is the a nice cheap GH KH test kit from API is certainly better then nothing unless you know your water is hard as heck already. Then skip it. If you have soft water or just don't know then use it and maybe give a little more GH then you really want to be sure.
LaMotte is nice. In my opinion, it is not necessary to spend that much unless you are doing research or are pretty sure you are having a calcium or magnesium issue even though your API is telling you everything is fine.
Edit: I forgot to mention the lowest minimum recommendation I ever heard was 30 ppm Ca and 10 ppm Mg. it can go up higher depending on the species of fish and plants. Most people say 4-5 degrees is "Nice" and some plants can go higher.
Most hobbyists use the GH test kit from API. They are unaware that is is a test that looks at Calcium and Magnesium combined. They are also unaware of the fact it does not tell them how much of each one. You could have 2 tanks with the same GH and wonder if you had any magnesium at all or any calcium at all. Usually, in FW, you have more calcium then magnesium. Both are important to plants.
We were wondering how close the GH test kit even is. Is it even worth getting.
Let's find out
I paid out the 51$ for my Hardness, Total Calcium & Magnesium, DRT kit from LaMotte.
(Code 4824-DR-LT-01)
I also have a combination GH KH test kit from API for around 7$.
Both kits are within there expiration and less then a year old.
For reference: 1 German Degree of Hardness = 17.857 ppm.
Calculator I use is here:
SaltyZoo's Alkalinity Reading Conversion (meq/l / dKH / ppm CaCO3) Utility
So let's get testing!
My tap water has a dGH of 8 as per the procedure in the API booklet. Really, it does a partial color change at 7 so I will call it 7.5 dGH.
The LaMotte uses the more accurate mg/l (ppm) measurement. So we will convert.
What LaMotte calls Total Hardness is the same as API's GH.
The result is 106 ppm which is 5.936 dGH. That is an error of 1.56 dGH or 27.93 ppm.
I did each test twice and I got exactly the same results both times so the repeatably is not an issue.
Some people would report this as a 20.8% error. That is actually pretty big as errors go. However, in a planted tank you can always just add a little more then you need and be alright. You can also watch the plants for signs of calcium deficiency which shows up as misshapen new leaves. Also, plants can die very fast if Calcium is depleted.
Just for kicks I decided to also break it down further into Calcium and Magnesium.
Calcium was 62 ppm (3.472 Degrees of Hardness)
Magnesium was (By Subtraction) 44 ppm (2.464 Degrees of Hardness)
The ratio should be 3 to 1. I am closer to 2-1. I don't believe it is a big deal as long as I have enough of both.
My conclusion is the a nice cheap GH KH test kit from API is certainly better then nothing unless you know your water is hard as heck already. Then skip it. If you have soft water or just don't know then use it and maybe give a little more GH then you really want to be sure.
LaMotte is nice. In my opinion, it is not necessary to spend that much unless you are doing research or are pretty sure you are having a calcium or magnesium issue even though your API is telling you everything is fine.
Edit: I forgot to mention the lowest minimum recommendation I ever heard was 30 ppm Ca and 10 ppm Mg. it can go up higher depending on the species of fish and plants. Most people say 4-5 degrees is "Nice" and some plants can go higher.
