Still Losing Chlorine

[Gary_PA]

Hey guys I am new to the forums,

After being pool stored for two years and spending close to a thousand dollars per year battling bi-weekly algae outbreaks I found this great site. I started using the BBB method a few weeks ago. All my numbers look good now accept for TA which I am working on. The water is crystal clear and CC is less than .5 usually around .2.

My issue is that I am still using about 1-2 gallons of 8.3% chlorine per day and I cannot pass the OCLT. I am losing 2-3ppm overnight. I started a SLAM on Sunday night and my test results for the following 2.5 days are below. Based on a CYA of 40 my target Shock level is 16. I have maintained that as best I could and last night even pushed it to 22 to see if that would help. This morning I was down 2.5ppm again. Any ideas? Do I just need to run longer? Should I be looking at something else?

	6/3/2017	6/4/2017
	Pool Store	My Tests
FC	2.5	4.4
TC	2.9
CC		0.2
PH	7.8	7.6
TA		160
AdjA	101
CH	436	350
CYA	65	40
TDS	900

	TIME	FC	Added
6/4/2017	5pm	19
	9pm	14	1Gal 8.3%
	11pm	18
6/5/2017	6am	15	1Gal 8.3%
	8am	15	1Gal 8.3%
	10am	18
	12pm	17
	2pm	18.5
	4pm	16.5	1Gal 8.3%
	6pm	21.5
	8pm	17.5	1Gal 8.3%
	10pm	19	2Gal 8.3%
6/6/2017	10am	15	1Gal 10%
	12PM	16.5	1Gal 10%
	2pm	20.5
	4pm	18.5
	6pm	17	2gal 10%
	10pm	22
6/7/2017	6am	19.5

Thanks,
Gary

 

[GaryT58]

A SLAM can take a while. To verify a few things:

Make sure your pump is running 24/7 to move water.

Make sure to be completely brushing pool at least once/day. Scrub carefully around space, lights, ladders, ...

Clean filter as needed.

Take morning reading before direct sunlight hits pool (will burn off chlorine) - 6am seems plenty early.

 

[spinPHD]

Have you looked behind the pool light? Oftentimes when people get as far as you (passed everything except OCLT) there is some algae hiding in behind pool lights and/or stairs.

 

[Gary_PA]

Thanks for the reply Gary,

I always run my pump 24/7. I know it is overkill but at least for now better safe than sorry. I have been brushing twice a day and have a Polaris 9550 robot running 3-4 times a day as well. I changed filter media just before SLAM and pressure has not moved yet so that should be good. Like I said it is crystal clear so I do not see filter being an issue.

Also wondering at what FC level are their diminishing returns? Do I jack FC up to 30? Will that make things go faster? Should I stick with the pool math recommendation of 16?

Thanks again,
Gary

 

[Gary_PA]

spinPHD,

I do not have any stairs, ladders, or railings. The steps are formed in the Shotcrete. I will triple brush around the lights. Thanks for the suggestion.


Thank you,
Gary

 

[drharris]

You could also take the light out to check behind it; brushing alone wouldn't be enough if there's some stuff growing behind it.

If it's not organics, it has to be water replacement. Do you have an autofill?

 

[Gary_PA]

drharris,

I do not have an autofill but I did just replace about 75% of my water last week in order to get CYA down. I was over 120 and now I am at 40. It has rained lightly the last couple days as well. Not to mention Worm-A-Palooza. Just vacuumed a couple hundred worms out this morning.




Thanks,
Gary

 

[Jezza]

Apart from looking behind the light niche which is a classic algae hiding spot I think Pool Owner Patience (POP) is required here.

Generally a SLAM is going to take a minimum of 4 or 5 days in my experience. This would be for a relatively clear pool perhaps with some cloudiness and a high chlorine demand.

 

[drharris]

Ah, ok. Unless it rained more than an inch while doing OCLT, that alone wouldn't explain it. By water replacement I meant like if you had a leak that was being topped off by an autofill, it could be FC loss from the leak. You might also try to help circulation by pointing returns downward.

I agree with Jezza that other than seeking out niches for algae growth like light, stairs, etc., it may just take a bit more time due to whatever was growing. It's frustrating when it's so clear (good main drain detail in that pic), but there's clearly something in there eating away at FC.

 

[Gary_PA]

Thanks Jezza,

I am not so good at POP. Good to know that 4-5 days is the norm. I was just watching the dollars fly out of my wallet again and not sure it was worth it. I will stay on course and keep to the recommended 16 ppm shock level for another few days. I will also remove the lights and check behind them. I think I know the answer but should I use an algicide to brush behind the lights or is brushing alone enough?

Thanks,
Gary

 

[Jezza]

Noooooo to the algaecide!!!

Brushing is perfectly fine with the elevated SLAM water. If you really want you can use a diluted bleach solution in a bucket of water.

 

[Gary_PA]

That is what I thought.

Thanks again,

Gary

 

[Gary_PA]

Quick Update

Beginning day 4 of SLAM. I jacked up the FC to 25ppm again last night at 10pm and this morning at 6am it was down to 21ppm so I am still losing too much chlorine overnight. I will stay the course.

 

[jjwalker]

You have organics somewhere....behind the lights or check the Polaris .... inside the hose?, cleaning bag?, it's somewhere you just need to find it

 

[Gary_PA]

I have checked the lights and they had a good solid seal. I took them apart anyway and brushed real good. i did not see anything but did it anyway. My Polaris is a robot so it has no hose and I bleached the waste basket (cleaning bag) just to be safe.

It looks like it just may be a matter of time. I will keep it going but have a question. It is supposed to get nice this weekend and the pool may finally be warm enough to swim. Is it safe to use the pool during SLAM with FC at 16-20?

 

[Jezza]

Yes stay the course and it is safe to swim up to SLAM level.

 

[Gary_PA]

SUCCESS!!!!!,

You guys are amazing. I was really starting to lose faith but after 9 days and 31 gallons of bleach it worked. I have included a chart of what my results looked like for others to get a better sense of what a SLAM looks like. I am losing less than .5ppm overnight now with .0CC. The only down side is that it looks like it will take about a gallon per day of chlorine to keep my levels up. I am losing about 3ppm per day to the sun. My new solar cover just came in so maybe that will help a little.

Thanks again for all the help. This is the best forum I have ever participated in. Everyone is knowledgeable and HWA (Helpful Without Attitude).

Date	TIME	FC	Added		Date	TIME	FC	Added
6/4/2017					6/10/2017	6am	20
	5pm	19				10am	18
	9pm	14	1Gal 8.3%			2pm	13.5	1Gal 8.3%
	11pm	18				6pm	16	1Gal 8.3%
6/5/2017	6am	15	1Gal 8.3%			10pm	19
	8am	15	1Gal 8.3%		6/11/2017	6am	17.5	2Gal 8.3%	1.5 OCLT
	10am	18				2pm	15.5	1Gal 8.3%
	12pm	17				10pm	14.5
	2pm	18.5			6/12/2017	6am	13	2Gal 8.3%	1.5 OCLT
	4pm	16.5	1Gal 8.3%			2pm	13.5	3Gal 8.3%
	6pm	21.5				10pm	18.5
	8pm	17.5	1Gal 8.3%		6/13/2017	6am	18		.5 OCLT
	10pm	19	2Gal 8.3%			10am	16.5	1Gal 8.3%	.2 CC
6/6/2017	10am	15	1Gal 10%			2pm	15	1Gal 8.3%
	12PM	16.5	1Gal 10%			6pm	18
	2pm	20.5				10pm	16.5
	4pm	18.5			6/14/2017	5am	16		.5 OCLT
	6pm	17	2gal 10%			10am	13		.2 CC
	10pm	22				2pm	11.5
6/7/2017	6am	19.5				6pm	10.5
	10am	15.5	1Gal 10%			10pm	10
	4pm	15.5	1Gal 10%		6/15/2017	6am	9.5		.5 OCLT
	8pm	16.5	2gal 10%			11am	8		.2 CC
	10pm	25				2pm	7.5
6/8/2017	6am	21				10pm	6.4	1Gal 8.3%
	10am	18.5			6/16/2017	6am	9.5		0 CC
	2pm	16.5	1Gal 10%					31 Gal Total
	6pm	16	1Gal 10%
	10pm	18.5			6/15/2017
6/9/2017	6am	20				TA	120
	9am	18.5				CH	325
	5pm	14	1Gal 10%			PH	7.2
	9pm	17.5	1Gal 10%			CYA	50

 

[Swampwoman]

Nice chart
You did a decent job of keeping it above 16 most of the time. Just so you know, I regularly find that when people can keep the dose from ever falling below Slam (without nuking, eg normally just a few points above) it will shorten the duration, because as they say, every minute you're below slam level, the algae knows you're not slamming