We bought a LaMotte test kit set--one for alkalinity and one for hardness. The alk kit is great- no problem reading the color change. However the hardness kit is driving me crazy. Total hardness is an easy read as far as color change. The calcium however, is another story. The color change is supposed to go from red to blue but the change never gets blue--only purple. We took the kit with us to the LFS and he showed us how to use it. He made the measurement using the change from red to purple. This change is very subjective as do you read at the first sign of purple or dark purple or what. Anyone having experience with this kit? We thought it was the most accurate but not the way we are having to judge color change.
LaMotte test kit driving me crazy!!
- Thread starter g. mcclean
- Start date
Sounds like the same reaction that the SeaTest and Salifert kits use. It's not easy. I found that I could get fairly good at seeing when the color stopped changing. It helps to add the titrant slowly, so you don't overshoot.
The SeaChem kit has a very definite pink-blue transition. I would never go back.
The SeaChem kit has a very definite pink-blue transition. I would never go back.