Taylor FAS-DPD Test Help

[buki5]

Ok, so seemingly the much simpler test compared to DPD but I'm getting a variety of measures. I have a k-2005 test kit but went online and found taylors FAS-DPD instructions...went to PS and bought 0870 adn 0871 to test CL via FAS-DPD.

Started using the 10ml test adding 2 flat scoops of 0870, mixed until disolved. Then doing drops until clear. Seemed to measure 22 drops at .5 per drop total of 11ppm. If anyone was monitoring my earlier "Hopefully-simple Cloudy water issue" they'll know my CYA is very high well over 100. So, In cleaning up my water went to a very high 20's CL level. Now have clear water and have been waiting for CL to drop down.


Reran the FAS-DPD test at the 25ml mark, again using 2 scoops of 0870 but this time the color is very light pink and I go clear at 50 drops which should be 50*.2=2.5ppm.

Need explanation and if possible "clearer" step by step instructions to get a good accurate, repeatable reading.

Outstanding forum for the ignorant....me.

Brian

[Watermom]

Take a look at this thread and see if it helps.

http://www.poolforum.com/pf2/showthread.php?t=6870

[buki5]

There are moments when you realize you should have gone to bed at least an hour ago.....
22*.5=11. Amazingly so does 50*.2...

Thanks for the help! I'd go to bed now if I didn't have work to do.

Brian

[sturev]

Reran the FAS-DPD test at the 25ml mark, again using 2 scoops of 0870 but this time the color is very light pink and I go clear at 50 drops which should be 50*.2=2.5ppm.

I think it says to add another scoop until it turns red...? also 50*.2 = 10

[AnnaK]

Seemed to measure 22 drops at .5 per drop total of 11ppm.

<SNIP>

Reran the FAS-DPD test at the 25ml mark, again using 2 scoops of 0870 but this time the color is very light pink and I go clear at 50 drops which should be 50*.2=2.5ppm.

50*0.2=10

Looks like a good set of results.