High Combined Chorine

[Clearly]

Is there a link somewhere for the bucket List procedure? Should I wait to let it come down on its own or start immediately?

[PoolDoc]

The only reason for the bucket test is to see how much chlorine it will take -- but it won't change what it takes at all, or make it easier.

But, if you want to do the bucket test, do this:

1. Add 4 boxes of borax (20 Mule Team brand, added slowly to your skimmer, pump running) to your pool. The conversion process goes more nicely at a higher pH.

2. Get a CLEAN 5 gallon bucket and a bathroom scale. Put the bucket on the scale, and weigh it. Add enough water to the bucket to increase the weight by 33 lbs (4 gallons) - PF:3640

3. Half fill a measuring cup with plain 6% chlorine bleach. Add 1 oz to the bucket (about 14 ppm). Mix, wait 15 minutes, remix, wait 5 minutes. Test the chlorine levels.

4. If the CC level is higher than the FC level, repeat the dose and process.

5. Continue until the CC level begins to be LOWER than the FC level.

6. Add one more dose, then mix and wait 1 hour. Retest. If the CC level is less than 1/4 of the FC level, this is your approximate finishing point.

7. Multiply the number of doses by 14 to determine the total approximate dose required to clean up your pool. Divide this number by 2.7 to determine the number of gallons of bleach required, or by 3.7 to determine the pounds of 68% calcium hypochlorite required.

8. With a gunite pool, you can tolerate VERY high chlorine without a problem. Add 3/4 of the bleach (if you are using bleach) at one time. Do NOT cover the pool; do NOT let the heater or SWCG operate.

9. If you use cal hypo, you must add it slowly via the skimmer, but you must make SURE that there are no tabs, trichlor, ionizers or other chemicals or devices between the skimmer and the filter. Make SURE the heater & SWCG are off. You may need to backwash several times, as the lime dust accumulates on your filter.

10. Again, during this process you MUST leave the pool uncovered, the heater off, the SWCG off, and the pump ON.

[Clearly]

Ben,
I am confused where you are getting the 14 and 2.7 numbers. My pool is 22,000 gallons or 2,816,000 oz. Four gallons in the bucket is 512 oz. By ratio, if I add one oz bleach to the bucket that would be equivalent to 5500 oz to the pool, or 43 gallons of bleach. Your numbers say a 1 oz dose is equivalent to 5 gallons of bleach, which is much better, but I am not following the math.
Additionally, according to the pool calculator, adding one oz bleach to 4 gallons will raise the FC by 121. I am not trying to question your theory I am just trying to get the numbers to make sense in my head, as I am a dorky engineer! Thanks.

[Clearly]

So I have attempted the bucket test. I calculated that 5mL (0.16 oz) chlorine in 5 gallons of water (15ppm) is equivalent to 5.5 gallons of chlorine in my 22,000 gallons. So my dose in my bucket is 5mL. Here are the results of my bucket:
Before any chlorine: PH – 8.0, FC – 1.0, CC - 18.5
After first dose: FC – 17, CC – 21
Second dose: FC – 32, CC – 33
Third dose: FC – 46, CC – 36

I figured the FC was high enough even though the CC wasn’t 1/4FC. So three doses at 5.5 gallons per dose is 16.5 gallons, but I added 14 gallons to the pool (a little more than 75%). Unfortunately, I used the entire 871 reagent durin the bucket test and before I could test the pool because the chlorine is so high. I’ll have to get some more tomorrow before I can test again. Hopefully Leslies has some.
These seem like some high chlorine levels! Does this seem like I am on the right track?

[PoolDoc]

I doubt Leslie's has any R0871, though you could certainly check. If it's much of a drive, I'd call first though.

But, you are right about the R0871 -- I had overlooked the fact that we need to warn people that the high chlorine & cc levels experienced during ammonia clean burn through the R0871 in a hurry. It's a bit of a problem, since there's no real fast way to get more. I just looked on Amazon, and this is probably your best bet:

Taylor FAS-DPD Titrating (Chlorine) 16 oz R-0871-E

You can refill your R0871 bottle, by popping the tip out (press your thumb on the side of the tip, while holding the bottle, and press), and then refilling. You might want to try doing so BEFORE you order the big refill, since if you happen to ruin the bottle, you won't be able to use the refill. Use CLEAN hands -- you don't want to contaminate the tip or the solution.

Also, if you'll store the pint bottle in the back of your fridge, where it's dark and cool, it should last several season.

Regarding your pool, I'd recommend going ahead and adding a 25 gallon dose of chlorine, at about 7 or 8 PM, so it has the maximum time work before the sun hits it. I'd also recommend putting in a couple of boxes of borax, first, to raise the pH a bit more (you reported 7.6).

You can use an OTO kit to monitor it. After the initial dose, it will probably give a dark orange brown results (~70 ppm). You do NOT want to swim in this till it drops to dark yellow, unless you begin adding stabilizer first. It won't hurt YOU, but 30 ppm of free chlorine, with no stabilizer, is a swimsuit killer! AND, 20 ppm of COMBINED chlorine WILL give you a skin rash, etc.

[Clearly]

PH isn’t an issue, my PH goes up very quickly. It was 8.0+ before I added the 14 gallons last night. Do I just let it stay high during this chlorination process and then add acid after the CC is down?
Are you suggesting I add 25 more gallons (in addition to the 14 I added already) or 25 gallons total?

[PoolDoc]

If the bucket sample was collected BEFORE you added the 14 gallons, then I'd recommend adding 15 gallons, rather than 25.

If you're pH is already near 8.0, you don't need to boost it.

[Clearly]

Just to put some closure to the thread, my CC is gone! I added 14 gallons a day for three days. Then More 871 Reagent came in and I was able to measure the chlorine, FC - 25 and CC - 0. Thanks for the support.

[Watermom]

Good news! Thanks for reporting back in with the results. Now, time to go swimming!

[Darkside]

I doubt Leslie's has any R0871, though you could certainly check. If it's much of a drive, I'd call first though.

But, you are right about the R0871 -- I had overlooked the fact that we need to warn people that the high chlorine & cc levels experienced during ammonia clean burn through the R0871 in a hurry.

just reading through some threads...

FYI - i went through one bottle of R-0871 real quick during the algae clean up. im also going through R-0013 ( almost ran out ) since i have high CYA and am draining/filling/testing every few days untill i get to an acceptable level. i was able to pick up R-0871 at pinch a penny ( .75oz ) and R-0013 ( 2oz ) at leslies. i doesnt hurt to give them a call to see if they have it.

congrats on getting cleaned up clearly!