New User Getting Butt Kicked By Algae

[TCP007]

Test came and here are my results:

FC = 22.5
CC = 1
PH = 7.3
TA = 200
CH = 170
CYA = less than 30. Dot was still visible after small comparator was completely filled.

I am reviewing the treatment tables, but wanted to post my results immediately. Thanks for suggestions in the meantime.

Additional note and question:

My chlorine results could be wrong or skewed. I took a few minutes to read some materials/tables AFTER my sample went from pink to clear. I then added more reagent until it went clear again, which added to a higher FC result. The initial calculation would've put my FC at 17.

Perhaps I need to wait a couple more days to test for chlorine, since I just super-chlorinated 2 nights ago. (?)

I think the other results are accurate.

[CarlD]

OK, since you have your K-2006, let's go over how to test for FC. I know this may be redundant but for those of us who have done the FAS-DPD testing for a decade or more it may help to review:
1) Rinse the test tube.
2) Point the tube opening DOWN and push it down about a foot under the water, then invert it so it fills BELOW the surface
3) Pour off water until it is at the 10ml line.
4) Add one scoop of DPD powder. The water should turn pink or even red. If it does, that's enough.
5) Add one drop of the 0871 reagent and swirl. Each drop represents .5ppm of Free Chlorine (FC). 2 drops=1ppm, 5 drops=2.5ppm, etc.
6) When the water goes clear, that's the last drop to add. I like to be certain so I put the tube on something white. If there's a tinge of pink I add one more drop.
7) Your count of drops gives you your FC level.

CC (Combined Chloramines):
8) To the SAME tube above, now add 5 drops of 0003 and swirl.
9) If there is NO pink tinge at all, you have 0 CC--that's good.
10) If there is any pink or red, keep adding the 0871 drops as before, but start the count from 0 again. 1 drop is .5ppm of CC. Do remember that if one drop is all it takes to clear the tube, your CC is .5 or LESS--it could be .2 or .4ppm. Usually, a CC of .5 is nothing to worry about.

pH is fine.
TA is high but for now, especially with your CH of 170, absolutely nothing to worry about.

CYA is low. Are you sure you ran the test correctly? Things to remember:
a) equal amounts of pool water and reagent 0013.
b) shake for at least 30 seconds.
c) hold the tube at waist level when you add the liquid.
d) Pour the liquid BACK into the squeeze bottle, then add it to the tube again to check
e) You can do d) several times over with the same liquid until you are sure of your reading.

Once you get your water clear, you can worry about lowering your T/A to the recommended 80-100 level, raising your CH over 200ppm (you have a gunite pool so 200-400 is recommended), and getting your CYA level up to AT LEAST 30ppm.

FYI: Di-Chlor powder adds CYA to your water--for every 10ppm of FC it adds, it also add about 9 or 10ppm of CYA. Tri-Chlor tabs add about 6ppm of CYA for every 10ppm of FC, but also are VERY acidic--which may hel your T/A adjustment later (see the next paragraph).

WHEN you are ready to lower T/A, you'll lower pH to 7.0-7.1 (you have a touch more wiggle room on the minimum than a vinyl pool, but 6.9 should be your absolute minimum), then aerate your water to raise pH back up. You'll keep doing this until T/A is in the 80-120 range. Aeration can come from a sprayer, kids splashing, or even just pointing the returns at the surface so they bubble. It's a ratcheting process, because T/A measurements rise and fall with the pH level and the ONLY way to raise pH without raising T/A back up again is by aeration. But that's for later.

[TCP007]

Thanks, Carl!

The instructions with the kit say to add 2 scoops of the powder. Wish I had known you only need to add enough powder to turn the sample pink/red. That must be why my FC reading was so high (?) so I will re-test this evening for sure.

I ran the CYA test properly with the correct measurements of pool water / reagent. I actually ended up filling my small comparator to the brim and the dot was still quite visible. Since the cylinder's lowest registered reading is 30ppm, I can only assume mine must be close to zero. This is not a surprise as I have known all along that my CYA is/was quite low, and definitely below 30. I didn't add it back to the sample bottle (squeeze bottle) but will keep that in mind for future tests. I know the sample is supposed to be somewhat "cloudy" after adding the reagent. It was quite obvious that my sample was not visibly cloudy.

My pool water is crystal clear now and has been since Friday. I will retest my chlorine this evening and post. Can someone tell me a good FC level at which to start adding Di-Chlor again? I have already re-supplied my floater with Tri-Chlor, which is slow dissolving.

[Watermom]

With a low CYA like you have, I'd probably wait until my FC was at 3-4 before adding more dichlor.

[CarlD]

I have to disagree with Watermom here (a rate occurrence) and say start using the di-chlor immediately as it will add nearly as much CYA as chlorine, and you need CYA.

Unless I missed something ....

[Watermom]

He last reported FC of 22.5ppm.

[TCP007]

New readings:

FC = 12.5
CC = .5
PH = 7
TA = 150
CH = 170
CYA = N/A

Chlorine results are more accurate this time. 1 scoop powder made a big difference, imo.
CYA: Same results. Small comparator was completely filled and I could still see the dot. I need to get that resolved.
pH is lower now. I tested it twice to be sure. I was surprised that it dropped that much in just a couple days.

Is it okay to start adding Di-Chlor, and will that also help to bring my pH up a little? I know it will help with CYA.

My pool is old, gunite. It has a bottom drain in diving end and 1 skimmer (in corner of deep end), and 2 returns that are both on the opposite wall (in the shallow end) right near the base of the wall. They don't have nozzles or any means of directing the water. I have no means of aeration to help raise pH, aside from keeping kids in there splashing around. Other aeration ideas are welcome!

Thanks everyone for your responses.

[CarlD]

He last reported FC of 22.5ppm.

So, I guess I did miss something. Don't know why I thought the FC was 0.......