Finally Received Gh And Kh Testing Solutions

[RainboWBacoN420]

I ordered API: GH and KH testing solution kits, I had received it in the mail today and I'm a bit confused on the final steps of picking up the results.
According to the directions, to test for KH, I must keep adding one drop at a time until the water in the test tube goes from blue to yellow, same for GH, except it's orange to green. Well, how yellow and green, exactly?
Until the water is tinted yellow and green? Or until it's a dark yellow and green? How can I know if I've added too many drops?
Here's what I tested in the 55 gallon:
GH: 90-125 ppm
KH: 90-125 ppm
Ph: 7- 7.2
 
I kept adding drops until the water int he tubes were a pretty dark green and yellow. So I may have done it wrong the first time around, I'm not sure, the kit didn't come with a reference or anything and this is my first time getting familiar with testing for GH and KH.
 
Advice appreciated! Thanks!

 

[boshk]

good question. I have the same thoughts too. 
Mine turns light yellow or green around 3 drops but I can keep adding and until 7 drops for a bright yellow or green. 3 vs 7 drops is a huge difference in ppm.
 
Also I found the ammonia test is the same, in the light it looks.....light whereas with light behind the colour chart, its darker.

 

[Essjay]

Its the change in colour not the intensity of colour you are looking for. If you have soft water, the colour changes after just a few drops. Because only a few drops have been added, the reagents are very dilute and the colour is pale. It is only with hard water - lots of drops needed - that you get strong colours.
If you have soft water it is easier to see the colour change if after adding each drop and shaking the tube you then remove the lid, put the tube on something white and look down into the tube. Because you are now looking through a couple of inches of water rather than half an inch looking through the side of the tube, the colour appears more intense.
The blue to yellow change of the KH test is easier to see than the orange to green of the GH test.
 
My GH is 6 deg and my KH is 4 deg which is how I know

 

[boshk]

Its the change in colour not the intensity of colour you are looking for. If you have soft water, the colour changes after just a few drops. Because only a few drops have been added, the reagents are very dilute and the colour is pale. It is only with hard water - lots of drops needed - that you get strong colours.
If you have soft water it is easier to see the colour change if after adding each drop and shaking the tube you then remove the lid, put the tube on something white and look down into the tube. Because you are now looking through a couple of inches of water rather than half an inch looking through the side of the tube, the colour appears more intense.
The blue to yellow change of the KH test is easier to see than the orange to green of the GH test.
 
My GH is 6 deg and my KH is 4 deg which is how I know

Thanks Sue
 
Mine should be around 3 then. soft water

 

[RainboWBacoN420]

So, it's only when the color changes from the first color to the last? As in, as soon as that color changes?
I think it only took about 5-7 drops to change color, I assume that would be semi-hard water. Where's the line that distinguishes soft from hard water? I'm guessing somewhere between 5-7 dGH...? 
 
Just taking this from the API reference chart it came with, it only goes from 1-12 dGH and dKH, so I would think that would be the standard or most typically found results for aquariums. 

 

[Essjay]

Different sources seem to say different things.
 
My water company gives the hardness as mg/l Ca, though it does allow conversion to other units. They say my tapwater is 34 mg/l Ca, which is the same as 85 mg/l CaCO3 (which is what test kits mean when they say ppm), and 4.76 german deg (the same as the API tester). Hmmm, it looks like my water is softer than last time I tested a couple of years ago (and the 2010 water quality report saved on my computer said it was a bit harder too). They also define this as 'moderately soft'.
 
The website also gives the boundaries for each 'level' of hardness.
Soft = 0 - 50 ppm or 0 - 2.84 deg
Moderately soft = 50 - 80 ppm or 2.84 - 5.68 deg
Slightly hard = 100 - 150 ppm or 5.68 - 8.52 deg
Moderately hard = 150 - 200 ppm or 8.52 - 11.36 deg
Hard = 200 - 300 ppm or 11.36 - 17.04 deg
Very hard = over 300 ppm or over 17.04 deg
 
 
According to their scale, your hardness fits into their definition of slightly hard.

 

[RainboWBacoN420]

Thanks! That makes more sense.
I'll do a retest today once I get home. I was looking up videos on it, and people add drops until the color is dense. I really wish it came with a color preference like the other testing solutions did, to at least get an idea of what the color should be once you've added enough to get the reading. 

 

[Essjay]

Ooops! Error in my last post

 
In the bands given by my water company, the second line should be
Moderately soft = 50 - 100ppm or 2.84 - 5.68
 
 
My excuse is that my husband was waiting to go out so I rushed it.

 

[RainboWBacoN420]

Ooops! Error in my last post

 
In the bands given by my water company, the second line should be
Moderately soft = 50 - 100ppm or 2.84 - 5.68
 
 
My excuse is that my husband was waiting to go out so I rushed it.

That's fine. That's actually what the recommended levels of hardness according to API. 

 

[Byron]

When I researched an article on all this, I came up with this chart which I think is perhaps a bit closer, though all terms are subjective:
 
0 - 4 dGH 0 - 70 ppm very soft
4 - 8 dGH 70 - 140 ppm soft
8 - 12 dGH 140 - 210 ppm medium hard
12 - 18 dGH 210 - 320 ppm fairly hard
18 - 30 dGH 320 - 530 ppm hard
over 30 dGH over 530 ppm very hard
 
The API GH and KH tests can be a bit confusing, sometimes due to the age of the regents.  But I agree with Sue's suggestion to hold the tube uncapped over white and look down.  When I do this, the change is pretty obvious.
 
Another good idea is to compare your results with the numbers from the water authority.  If they are relatively close, you are probably OK.
 
Byron.

 

[RainboWBacoN420]

Well, I looked up the general hardness of the tap water in my town, and it's a range of 109-177 ppm, as of 2014, so things could be entirely different now. But if it's similar to this years, then that makes sense.
Again, I'm going to retest the hardness in my tanks and see what I get, but I'm pretty sure it's 90-125 ppm. To API that's very hard, but on your chart, that's very close to what people on YouTube have addressed about water hardness. 
 
And I think I'll take that approach next, I always hold the tubes against a white background, but never thought of looking down uncapped. Thanks.

 

[RainboWBacoN420]

So, I retested my 55 gallon and here were the results:
4 dGH
2-3 dKH
 
So my water must be pretty soft then. I did what Sue said, and looked at the tube uncapped on a white background and only took down the results on the instance of the color changing. 
 
According to the pamphlet that was provided with the kit, these conditions are suitable for neons and corydoras, which are presently in my tank. 

 

[Byron]

So, I retested my 55 gallon and here were the results:
4 dGH
2-3 dKH
 
So my water must be pretty soft then. I did what Sue said, and looked at the tube uncapped on a white background and only took down the results on the instance of the color changing. 
 
According to the pamphlet that was provided with the kit, these conditions are suitable for neons and corydoras, which are presently in my tank. 

 
Yes. Soft water fish will be fine; avoid the harder water species such as all livebearers, African rift lake cichlids, some (but not all) of the Rainbowfish, and a few others.  Generally, fish naturally found in South America, SE Asia and Central Africa are soft water.

 

[RainboWBacoN420]

 

So, I retested my 55 gallon and here were the results:
4 dGH
2-3 dKH
 
So my water must be pretty soft then. I did what Sue said, and looked at the tube uncapped on a white background and only took down the results on the instance of the color changing. 
 
According to the pamphlet that was provided with the kit, these conditions are suitable for neons and corydoras, which are presently in my tank. 

 
Yes. Soft water fish will be fine; avoid the harder water species such as all livebearers, African rift lake cichlids, some (but not all) of the Rainbowfish, and a few others.  Generally, fish naturally found in South America, SE Asia and Central Africa are soft water.
 

This helps a lot. Thank you for this valuable information.