Aimee is correct ... there is no "half drop" If one drop clears it, then your CC is < 0.5 which is all that matters.
Going it alone. Need help.
- Thread starter simonmoll
- Start date
So if I do CC test and it takes one drop to change color to clear that would mean CC was zero? Whereas there is clearly some CC as there was a red tinge that went with one drop.
- - - Updated - - -
sorry missed post from jblizzle
- - - Updated - - -
sorry missed post from jblizzle
Technically, if you want to follow what Aimee said exactly (like for other tests), you would start with some pink. Add 1 drop that appears to clear it, add a 2nd drop which results in no change, and thus you would say CC = 2-1 = 1 drop = 0.5ppm ( or really something between 0 and 0.5)
I have never had a color change on the addition of the r-ooo3 reagent after testing chlorine. So if you saw a color change at all, I think that indicates "some" CC's. But if I understand, your drop test then concluded there are "some"but less than .5
Mine is usually 0 as well, but this morning after doing an OCLT I did see a hint of pink which was gone in 1 drop. Likely due to all the tree garbage that is falling into the pool recently and lack of sun to burn it off.
If you stop doing the FC test when the sample turns colorless instead of adding one more drop with no change, then you're more likely to get a tiny bit of pink at the start of the CC test. It's really not worth trying to measure sub-drop levels. If you care, use a larger sample.
I've only seen real CC in my pool once. I repeated the test just to be sure and then went after the problem.
I've only seen real CC in my pool once. I repeated the test just to be sure and then went after the problem.
Thanks for those insights.
Doing the FC test I am always concerned about the amount of R-0870 powder I use as the instructions say one "heaping" scoop which I take to mean a heap of powder above the scoop level. Does it matter that much?
ANYWAY todays early morning readings:
FC 9.5
CC <0.5
PH 7.5
So I think OCLT test passed. Pool looks good and I was pleasantly surprised to see PH seems to be at a good level.
Please confirm that once the FC level has reduced to 5 (CYA is 38) I need just to maintain it at that level and keep PH in 7.2-7.6 and I should not have anymore algae?
A couple of further questions:
The color test for TC only goes up to 5. So if my CYA rose how would I check TC on a daily basis?
As we have very bright sunshine here would it help to get the CYA up a bit? I bough lots of chlorine for the shock that I haven't used but if increased CYA would reduce the amount of chlorine I need to use it would help as the 5.25% (which is all I can buy here) cost US$3 gallon.
- - - Updated - - -
Just a note: I did FC in the dark at 6:45 last night:
FC 9.5
CC < 0.5
Doing the FC test I am always concerned about the amount of R-0870 powder I use as the instructions say one "heaping" scoop which I take to mean a heap of powder above the scoop level. Does it matter that much?
ANYWAY todays early morning readings:
FC 9.5
CC <0.5
PH 7.5
So I think OCLT test passed. Pool looks good and I was pleasantly surprised to see PH seems to be at a good level.
Please confirm that once the FC level has reduced to 5 (CYA is 38) I need just to maintain it at that level and keep PH in 7.2-7.6 and I should not have anymore algae?
A couple of further questions:
The color test for TC only goes up to 5. So if my CYA rose how would I check TC on a daily basis?
As we have very bright sunshine here would it help to get the CYA up a bit? I bough lots of chlorine for the shock that I haven't used but if increased CYA would reduce the amount of chlorine I need to use it would help as the 5.25% (which is all I can buy here) cost US$3 gallon.
- - - Updated - - -
Just a note: I did FC in the dark at 6:45 last night:
FC 9.5
CC < 0.5
No
You have passed the OCLT so that confirms completion of your SLAM. Let FC drift down to maintenance levels.
CYA will only go up if you put CYA in the pool....I would leave it where it is for now.
Your excess chlorine is easily consumed just by maintaining FC around the 5 ppm level.
Congrats on your clear pool.
Your questions indicate you do not yet have a really strong grasp of the chemistry involved.read "The ABC's of Pool Water Chemistry" up in Pool School again. Stay on the forum and read other threads about clearing a green/murky pool. It will come together for you very soon.
All was going well for a week or so when I noticed light green on the concrete steps. Brushed it and sure enough algae again.
So I am slamming again.
I scrubbed the pool this morning and then went into the pool to hand scrub some tiles above the surface that had green in the grout. I also found that in the skimmer there was a small patch about the size of a quarter of bright green algae. It was well above the waterline but would get splashed when anyone was in the pool.
I then looked at the coping stones and some of them have lost the smooth surface and have lots of holes and cracks and in one area of the pool (nearest palms) they were black with mold on the underside which would get wet when anyone is in the pool. So I scrubbed all of it and found that there was a green tinge when I did this until I completely scrubbed the mold away
(into the pool).
So I am going to replace the offending coping stones and check the skimmer more thoroughly.
Any thoughts from those with experience?
So I am slamming again.
I scrubbed the pool this morning and then went into the pool to hand scrub some tiles above the surface that had green in the grout. I also found that in the skimmer there was a small patch about the size of a quarter of bright green algae. It was well above the waterline but would get splashed when anyone was in the pool.
I then looked at the coping stones and some of them have lost the smooth surface and have lots of holes and cracks and in one area of the pool (nearest palms) they were black with mold on the underside which would get wet when anyone is in the pool. So I scrubbed all of it and found that there was a green tinge when I did this until I completely scrubbed the mold away
(into the pool).
So I am going to replace the offending coping stones and check the skimmer more thoroughly.
Any thoughts from those with experience?
This evening
FC 10
PH 7.4 (put muriatic acid in this morning)
- - - Updated - - -
so I put muriatic acid in a bit too early. I'll remember next time.
FC 10
PH 7.4 (put muriatic acid in this morning)
- - - Updated - - -
so I put muriatic acid in a bit too early. I'll remember next time.
What were your test results after your last SLAM and right up before you found all this algae and mold? Were you keeping up on testing and adding chlorine? Are you brushing your pool regularly? Brushing is something a lot of people put to the side... it needs done more often than not.
I think I let the FC level get down to 1 for a day or so and the algae started a couple of days later even though I had put FC up to 4-5.
Have to be more careful.
However I find it difficult to read the Taylor Total Chlorine yellow color test and even harder with the PH test. I do the FC test more often than not so I am sure of the FC level.
- - - Updated - - -
I have been brushing during the slam and once a week and testing daily.
Have to be more careful.
However I find it difficult to read the Taylor Total Chlorine yellow color test and even harder with the PH test. I do the FC test more often than not so I am sure of the FC level.
- - - Updated - - -
I have been brushing during the slam and once a week and testing daily.
I always use only the fas-dpd test for my daily testing. It's easier to know for sure and I am a perfectionist. Anything I can know precisely makes me happy.
glad to know I am not the only one who doesn't like the OTO test. I also often have problems determining the PH although this morning it was very clear.
FC 10 so no loss overnight.
PH 7.4
and pool crystal clear
FC 10 so no loss overnight.
PH 7.4
and pool crystal clear