GH test results?

[mattrox]

I have an API Freshwater Master Test Kit and I was wondering if anyone had difficulty picking the yellow to green end point of the General Hardness test? I got like 25 drops and still thought the vial looked yellow. Do I have liquid rock in my tank?

My KH was 4 degrees.

 

[QTOFFER]

How old is the kit? I noticed the same thing with a kit that was about 3 years old. After 12 drops, the vial was still yellow. I knew that this couldn't be right because my water always tested on very soft side in the past. I bought a new kit and achieved the green endpoint with only 2 drops.

 

[mattrox]

I suspect that the age of the kit is a factor. I only really use pH, nitrite and ammonia from that kit anyway and they work.

 

[rkilling1]

My API GH kit only lasted about 12 months, tops, before I had to replace it. It was doing the exact thing that you describe. I purchased a new kit and my GH was 4 (as expected), but was adding 30 drops or more with the old one.

 

[mattrox]

I really don't need to know my GH at the moment, I was just curious so tested. I'll get around to replacing the GH kit some day. They are relatively expensive comparitively here in Aus....

Thanks for your input.

Oh yeah, which other tests are suseptible to age? Are the pH tests prone to this? The nitrite seems to be working still, I have used up and relpaced the ammonia kit.

 

[JeffreyL]

Someone here posted they had contacted API about expirations of test reagents. They were told to look for the lot no. on the top of the front label. It will have a number such as 28B0706. The last 4 numbers is the month and year of manufacture. In this case, 07 of '06.

API said the reagents are good for 3 years from the date if sealed and unopened. Once open , they are good for 1 year. I have taken to writing the date on the bottom when I open them.

Now it is likely the solutions are good for some time after the given expiration date. How long is anyone's guess. Something potentially critical such as an ammonia test I think I will replace when it expires.

HTH

Jeff