OTO chlorine Test (Questions)

[scott.MI]

I'm just wondering something about the OTO chlorine test.

In the details of the kit it says "normally used daily".
I also read in the extended test directions " Above 2 (ppm) accurate readings become difficult and the precision is very low. If its not precise above 2ppm and recommended levels are 3-7, I just can't figure out any time to use this chlorine test. Does anyone use it to decide how much chlorine to add or just as a quick simple look to make sure its not at 2 or less?

So who uses it daily?

Who uses it when, why, how often?

Who says if I'm getting my testing stuff out, I mine as well do the accurate one and do the FAS/DPD test instead?

 

[duraleigh]

I use it daily. As part of my "Quick" routine just to check that chlorine DOES exist in my pool and that it is roughly at the level I expect it to be....not too dark yellow and not too light yellow. Good enough reassurance for me and, over time, you can develop a more practiced eye so I pretty much know within a couple ppm where my FC is.....the test takes 15 seconds.

You are welcome to test more precisely and use the FAS/DPD daily and many prefer that. No harm, it just takes more time to complete.

 

[ship of fools]

I never use mine ..... i found it was not even close to accurate and the FAS/DPD test is so simple i just use it.

I don't even test daily ...... half a gallon or so of 8% bleach every day and i am all set

 

[Durk]

I never use it, either. I know if I have any chlorine before I test, because I stay on top of my levels. I always do, unless something has gone wrong, and in that case, I need to know the exact number. So OTO is pretty much a useless waste of time for me. Plus I get to use my SpeedStir with the FAS-DPD.

 

[Butterfly]

The OTO is a bulletproof test for the presence of chlorine.

 

[Isaac-1]

I am also in the rarely use it camp, I use the FAS DPD wtih speed stir, usually every other day or so, but I do have automatic chlorine injection. On occasion I will run it as a sanity check against the FAS-DPD test though.

 

[duraleigh]

Plus I get to use my SpeedStir with the FAS-DPD.

 

[msgtdan]

I use the OTO as a cross check and under certain conditions to see if I need to do the FAS check. Example: day before yesterday I was weed eating around the pool and saw some of the clipping go into the pool so I took FC up to ~10. I then put the solar cover back on and left it. Yesterday was cool and overcast when the OTO read higher than 5 FC I just stopped there and left it alone. We have similar conditions here today, so tonight when I check if it's still over 5 I'll walk away from it again, if not I'll test with FAS and see how much it needs.

 

[ship of fools]

I forgot to add that mine is woefully inaccurate ...... it might read 1 or 1.5 when the chlorine is 5 or 6.

I got all scared and nervous one time that my chlorine was so low (and i was so off base ) then i used the fas/dpd test and i was dead on.

Haven't touched it since

 

[chiefwej]

I use OTO and pH tests daily, then FAS/DPD and other TF100 tests (except CH and CYA) weekly. Those two tests only about once a month.

 

[duraleigh]

I forgot to add that mine is woefully inaccurate ...... it might read 1 or 1.5 when the chlorine is 5 or 6.

Nitpicking a bit here but it is difficult for the OTO to be extremely inaccurate. It is usually lack of experience and practice with that test that makes it hard to judge. I can easily get withing 2-3 ppm and that's w-a-ay good enough for the purpose for which I use it.

 

[Durk]

I use the OTO as a cross check and under certain conditions to see if I need to do the FAS check. Example: day before yesterday I was weed eating around the pool and saw some of the clipping go into the pool so I took FC up to ~10. I then put the solar cover back on and left it. Yesterday was cool and overcast when the OTO read higher than 5 FC I just stopped there and left it alone. We have similar conditions here today, so tonight when I check if it's still over 5 I'll walk away from it again, if not I'll test with FAS and see how much it needs.

Relax. Both my pools, going back to 1946, have had grass growing up to within a foot of the water. Lots of clippings go in every time I mow. I never shock, ever, except at open. Grass may be green, but it's not algae and doesn't seem to eat much chlorine.

 

[ship of fools]

I forgot to add that mine is woefully inaccurate ...... it might read 1 or 1.5 when the chlorine is 5 or 6.

Nitpicking a bit here but it is difficult for the OTO to be extremely inaccurate. It is usually lack of experience and practice with that test that makes it hard to judge. I can easily get withing 2-3 ppm and that's w-a-ay good enough for the purpose for which I use it.

I posted about this way back when it happened and if i remember correctly it was suggested that i may have had weak reagents ...... in any case i just do the fas/dpd test which takes me all of 1 minute

 

[ship of fools]

Here is my post from way back

large-discrepancy-in-cl-tests-t46507.html

I read 0 on the OTO test and 4 on the FAS/DPD