Question about CH test with tf100

slayer

Active member
Aug 26, 2011
25
#1
I ran a Calcium Hardness test with the tf100 kit. I filled the cylinder to 25ml. I added the 20 drops of r-0010. Then added 5 drops of r-0011L. The sample was suppose to turn red but it turned a pale pink. Then I added drops of r-0012. At 25 drops, the sample became clear. I continued to add and stopped at 70 drops and the sample never turned blue. I then redid the sample adding 2 drops of r-0012 prior to adding R-0011L in case of the presence of copper but I had the same results. Do I not have enough calcium to turn the sample red or do I have another problem?
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
20,327
San Dimas, CA (LA County)
#2
The exact shade isn't as critical as the change. When it went clear is probably when it turned blue. You can always add a few extra drops of the R-0011L to get a deeper color. Then the color change should be easier to see. Also, how old are those reagents? If the R-0011 bottle is discolored at all, the stuff inside has gone bad.