First Time Algae Warrior

[Lucian]

Hi,

Last Friday noticed some green patches on the bottom, water was still clear.
I cranked up SWG to super-chlorination level, run it all night long then Saturday morning added 1 lb of HTH Extra shock as per pool store's advise
Continued to run SWG another 10-12 hrs or so
Sunday morning all look nice and dandy , no signs of algae.
I shut down SWG to 0 thinking to lower the FC to normal level
Green thing came back after 1-3 days , again not a lot , and pool was still very clear.
Cranked up again Supechlorinator and my current readings based on store check are :
FC 15
CC 0
PH 8.2 ( although independent lab gave me 7.8 )
TA 115
CYA 39
Phosphate 23
Algae still slightly visible.

Bought PUROX Liquid ( 10.8%)
I am thinking to attempt this:
1) Add Stabilizer to bring CYA to 70-80
2) Run pump overnight
3) Add approx. 5-6 liters of Purox to bust FC by another 13-14 ppm to a total of 26-28 PPM
I need to close the pool in 1-2 weeks and I am not so sure if that is the best strategy or just run superchlorinator , brush, vacuum, filter and hope the algae will be gone by then.

 

[mknauss]

Do not raise your CYA.

You need to SLAM Process. You must have a FAS-DPD test for FC to do this. For that, you need a proper test kit. In Canada, you can get the Taylor K2006C.

If you do not have that kit, then you will not be able to get your pool water algae free prior to closing.

But regardless, do not add any CYA. And if you close without doing a SLAM, then get a test kit over the winter and be ready in spring to SLAM.

 

[KS Mike]

I don’t have the expertise many here do, but since no one has replied yet.....

I would not add any CYA. Doing so would just require you to maintain higher SLAM levels. If your not familiar with the SLAM method, check out pool school. Run pump 24 hrs a day and continue the SLAM until you pass all the criteria. I turn my SWG off during a slam as I think it is easier to get accurate results on the progression and passing the overnight free chlorine loss test. Brush the pool daily (or more) during the slam.

If you don’t have an accurate test kit that has a DPD FAS chlorine test, get one.

 

[Lucian]

Thanks for the feed back. I could not get my hands on a decent test kit ( K2006) but I still attempted a version of treatment ( perhaps a light version of SLAM, if that makes any sense):
1) I collected sample of water at 7 pm last night
2) Brushed pool walls and bottom. Back wash and rinse filter
3) Added 5 litters of bleach (10.3% chlorine), SWG set to 0
4) Started to rain
5)Collected another water sample around 9 pm
6)More rain
7) Woke up next morning before sun hit the pool and collected another water sample.
8) More brushing, water looks clean and clear, just a few small debris at the bottom
8) Pump is running continuously all this time, Water and Air Temp are at 64 F
Took all 3 samples to the pool store and tested all 3 samples. Bellow are the results.:

	7:00 PM	RAIN STARTS	9:00 PM	RAIN	7:00 AM
Before Adding Bleech ( 10.3% Chlorine)		2 Hrs After adding 5 liters of bleech		10 hrs after bleech addition
FC	11.33		18.47		18.69
CC	0.21		0.23		0
PH	8.1		8.6		8.5
TA	117		115		115
CYA	41		43		43
PHOSPATE	45		222		171

Questions:
a) Despite FC not reaching the indicated SLAM levels, but based on no drop in FC and 0 CC, could it be that I am out of the woods ? No more algae ?
b) Should I add another gal ( 5 L) of bleach just to play safe ?. Next few days will be cloudy and rainy and I suspect it will be very difficult to drop the chlorine level from such high level as I would like to attempt to use the pool one more time next week-end ( heating it up first)

 

[mknauss]

I would add the additional bleach today and see how it looks in a few days.

I still suggest you get a proper test kit over the winter. You can have one shipped to a mail drop store at the US border and drive over to get it.

Take care.