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I have one of those GH test kits from Aquarium Pharmaceuticals (API), and according to their instructions, draw a sample of 5ml water into testtube, and then add 1 drop of test solution at a time.

Initially, water will turn orange, and count number of drops till water turns green. If water turns green after first drop, water hardness is 1dGH.

However, my problem is that after the first drop, the water hardly turns orange! And that's not just my opinion. other people i've asked to determine whether i'm colour blind agree that the colour is not orange. So now, after 1st drop is added, the water in the tube is a VERY FAINT green, and as i add more drops, it turns into orange, then a very dark orange. after i've added about 20 drops, i just give up, figuring i'd never reach the endpoint.

Anybody have solutions to this problem? I can go out and buy another kit, but are there kits that have a different type of colour change, ie: one that involves a more obvious colour change?

oh P: I have no problem when doing tests for KH because the colour change is from blue to yellow, which is way more obvious than turning green into yellow.

Hi,
Technically, when the water shifts color from the faint
green to a orange, that is the reading you should record.
Any additional drops just overload the reading so to speak.

This method is called Titration, and THE point at which
the solution changes color, even faintly, is the pivot
point and the reading.

Be sure to be in a well lit room when doing the tests, that
will help you discern the pivot point.

Frank.


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

I have the same problem with the API GH kit. My wife is a chemical engineer and neither of us can read it.

lol yay it's not just me who can't read it! maybe i'll just go and hunt down another gh test kit from another company..

I suspect that our GH is very low and the color change happens before enough drops are added to make it easily seen.

I did the test 8 times with 8 different tubes to compare them. 1st tube had one drop, 2nd had 2, etc. I laid them all on a white piece of paper and walked around the house to view in different lighting - even outdoors. The first one was "orangeish" and the last few were definitely green but I still couldn't tell for sure what the correct reading was. If you are going to try this, make sure you mix after each drop per the instructions. Adding multiple drops at once to save time can mess up the results.

After I moved last year, my pH was very unstable which lead me to purchase the kit. I only check KH now.

lol wow 8 test tubes huh! yeah initially i thought like the water was really soft, but then i added like 5teaspoons of blue crystals (supposedly meant to harden water) and results pretty much the same.

Maybe i'll try those test strips next time, although I've heard that generally strips are less accurate than liquid test kits - still, i think any strip will be easier to read than what i've got now! l0l

Hi,
Actually, the titration method is much more accurate
than the strips. With test strips you can "ball park"
the figure, but with the liquids or dry powder test
kits, the results are much more accurate.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--