If you own API GH test or Salifert kits read this...

[nsamuel]

I bought a API KH/GH test kit about a month ago. And a salifert phosphate kit..... I have issues with both of these. The API GH test does not produce the colors im expecting. The manual says first drop should turn water to orange and titration is complete when water turns green. Out of bottle this liquid is dark green. I dont see a crisp orange on first drop. Water turns light yellow in color and the yellow gets stronger with subsequent drops. Around 7th drop or so, water starts turning into yellowish/green, but not a clear green or clear yellow. The yellowish orange of the beginning drops is still present up till about 10 drops. Then the yellow seems to go away around 10-12 drops, and i have a light green color in vial, but i was expecting a good green color (as the manual does not say light green color). Looking at the water test report of my water company, i know that my GH should be around 160 - 180 range and i was testing my tap water to check things out. I kept adding drops till 25 drops, to see if it would get any darker, but no luck. The color remains pretty much as it was around 12th drop. Does anyone ever see the green color, or only a light green is to be expected ? I checked date on bottle and it says 1207 so only 6 months old since manufacture.

I have different issue with my salifert phosphate kit. The kit came with a paper color chart. It is so easy to ruin it with water droping onto the paper. With such a expensive kit, i was expecting salifert to give a decent color chart made of plastic. Are all salifert kits made with paper printed color charts ? Its so hard to tell the different between 0 and 0.3 in the colors. Any comments from owners, appreciated.

 

[OldMan47]

With the API test kit you are looking for the first clear color change. You would expect a reading of about 10 for the ppm your water company claims and as you say you get a clear color change at that point. There really are only the two colors and a transition that is easy to recognize between the two. When you see the yellow go and the green dominate, you are at the end point and are measuring between 10 and 12. Mine measures almost exactly 12. The descriptions are not very good in the directions but the color change is easy to spot.

 

[nsamuel]

Thanks for the reply. I was expecting more people to use the API GH test. How dark is your ending green for the GH ? I get the yellow first (not clear orange) and at some drop and shake, a shade of green starts. Faint green. After this, i have wait for the yellow to disappear completely. The yellow does disappear after about another 5 - 8 drops. So, the transition to green is not easy as you describe. (Note that the transition is much more easy to spot in my KH test kit that came along with this one.) The end color is only a light green, thats nowhere near the dark green of solution thats in the bottle. I would guess my green is only 25 to 40 % of the darkness i see in the green of the bottle. How close is your ending green compared to the bottle solution ? Do you see orange anytime during the process ? Thanks for the reply.

 

[Draal5]

I used to use that kit. I now use a TDS meter. you will see a slight change as the chemicals react but you are done when the color changes completely to green and NO yellow.

This is normal.

 

[nsamuel]

Draal, my ending color is not really green. It seems like a pale green (with a very very faint hint of yellow in it, that does not go away completely, even after 25 drops). So i assume that the best i will get is that shade of green. How green is your ending green color when compared to the green solution in the bottle ? I hope you remember the times when you used your API GH test kit.

 

[Draal5]

I just did a Test so I could give an accurate color not just from memory.

you get a yellow green not a dark green. when I just did it it went from yellow to an orange to yellow green but you can definitely see the color change.

hope this helps

 

[nsamuel]

I wanted to update this with some new info i have. I did a retest yesterday with different water body. Also note that when i first did the test, the bottle had been just opened fresh. So, the air exposure of the liquid had been nothing when i first tested with it. I dont know if this means anything, but note that once the bottle is open, there will be a little air that will enter the bottle. But, whatever maybe the reason, when i did the testing again with this GH kit, the color changes were easily readable and as described by Draal. The first drop produced a faint orange. The second and third drops intensified the orange (this time i didnt have the yellow tint in the orange that i got during my first test, soon after opening the bottle). The 6th drop clearly produced a light green, which took away 99% of the orange. So, the end of test was clearly readable, as a light green. Its not anywhere near the dark green that is the color of the solution in the bottle. Hopefully this will help others who have had similar trouble with GH test kit.