- Mar 2, 2019
- Reaction score
- Review score
- +0 /0 /-0
Glad to hear it worked!I decided to just attempt to make another batch of solution rather than worrying about how I had messed up. This time forewarned with the fact that I am using a 0.1N standard, I mixed 25ml of 0.1N with 1L of RODI. On my first test of the new standard, I got some really low reading (around what I had before). I re-tested, but with better light and I stopped as soon as the test changed to purple. When I compared the chart, 7.0 dkh. Yay! What I realized is that I had been going too far past the colour change. I was shooting for pink, but the change from blue to purple seems to be the correct point.
I went back and re-tested my tank water, being more careful to nail the colour shift, and got a reading that matched my automated tester, which is what I have been trying to validate.
Now I can crank up my CaRx effulent being assured of the numbers I am targetting. I was able to use the 7.0 dkh standard to not only validate the test, but to validate the tester (me). So a success all around.
One comment about what you described. With the Salifert test, going way past the end-point would increase the apparent alkalinity, not decrease it. I'd double check to make sure that you're correctly interpreting the syringe readings with respect to Salifert's alkalinity chart.