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Wayne LaBanca
05-31-2006, 11:15 AM
OK, first year opening the pool. Here are the current numbers:

12,200 AG
CYA <30 (Still see the dot at 30 but it is cloudy, I'm assumin the 10-20 range)
PH > 8.4 (Again, off the scale)
Alk 60
FC this morning was 4, shocked again to 12
CC 0

I opened the pool yesterday morning, very green but not stinky. Vaccumed to waste (blind) then added CL to bring the reading to 12. Vaccumed again once I could see "the dark mass" in the middle. Hit it again with cl 6 hours later, it had dropped to 2. Hit it one more time in the evening. As you can see above, it held some cl over night so I feel my CC reading of 0 is acurate. Right now the water has that wash water white cloudiness look to it. The filter (sand) requires a backwash every few hours as of right now.

Is the white cloud the dead algae or is the high pH causing this? I'm assuming that this is what is causing the filter to need the frequent backwashing and leaning towards the dead algae.

Now,
should I adjust the pH first and then adjust the alk or the other way around. Two schools of thought here:

1. Adjust the pH first as the Alk will make it more difficult to change with a higher reading.

2. Adjust the Alk first because the pH will swing too rapidly to get an idea of where the adjustments are taking it.

Thanks,
Wayne

PatL34
05-31-2006, 01:44 PM
Add the Baking Soda first about 6lbs, which will raise your pH, and then muriatic acid to bring it back down to 7.2 -7.6. Aim for about 100 ppm TA with baking soda.

Continue to backwash as necessary to bring the cloudiness down.

Bring up your CYA to 50 ppm by adding 4 lbs through the skimmer and run 24/7 until it is all dissolved. Do not backwash during this period.

Use Mike Smith's Bleach Calculator to help you know how much chemical to add. Search for "Bleach Calculator" without the quotes.

Pat

CarlD
05-31-2006, 01:57 PM
I must disagree.

Your pH is WAY out of control. Bad enough to cause all sorts of problem. Add acid to lower it into the mid 7's (7.3-7.8) It MAY bounce around a bit, but it probably won't.

Meanwhile, don't stop shocking your water just yet. I would keep my chlorine at shock levels until it is PERFECTLY clear. Just because CC is 0 doesn't mean you cannot get another outbreak. It just means that at the moment, algae is dead but you aren't "there" yet. Now is the time for patience.

When pH and chlorine are under control, THEN you can add baking soda. I would start with 1 lb, not 6. Then wait 24 hours, check T/A again, and add another pound. Keep doing this until your reach 100ppm. You can add more, but you don't want to go over your target. THE TRICK TO MOST CHEMICALS IS TO GO SLOW! THIS IS ESPECIALLY TRUE for pH adjustments.

PatL34
05-31-2006, 02:32 PM
Carl,

I was under the impression that the TA acted as a buffer to prevent the pH flying all over the place. I was aware that the pH was at 8.2, but was considering stability against high pH in this instance.

Just my interpretation of the situation.

Pat

Wayne LaBanca
05-31-2006, 03:05 PM
Update:
Went home for lunch and the water is getting clearer. I can make out the bottom now and the filter was only running 3 lbs high after 4hrs as opposed to the 8-10lbs yesterday.

I will get the Muriatic going tonight to get that pH under control. I know it's through the roof and thought it may be contributing to the cloudy water issue. I was still at 3ppm on the cl after 4hrs of sun so were still OK. Probably should have dosed in more cl though.

Wayne

Wayne LaBanca
05-31-2006, 07:24 PM
Update:
OK, shocked again. pH has come down to 7.8, holding off on the Muriatic. I can see the bottom now without straining so I think things are going well. Thank you for the input all, I watched the threads last year and saw how much patience plays a part and watched new comers not practice that. I now realize how hard that can be when you are new. :)

Wayne LaBanca
06-01-2006, 06:37 AM
Update:
FC held to 9 overnight (no CC) and water is clearer yet. :) pH is 7.3 before sunrise this morning so I am now dosing Alk to get it stable, currently at 50ppm. Added 2lbs of BS, should need another 6lbs or so to get to 100.

Question: Why did the pH drop? there has been no rain and I am using 12.5 liquid bleach.

Wayne

PatL34
06-01-2006, 08:40 AM
Have you checked your Alk during all this time, if not you need to bring up to 100 ppm slowly as CarlD mentions above. I think that is why your pH keeps dropping.

Pat

Wayne LaBanca
06-01-2006, 10:19 AM
Have you checked your Alk during all this time, if not you need to bring up to 100 ppm slowly as CarlD mentions above. I think that is why your pH keeps dropping.

Pat

Yes, it has been at 50 from the start. whatever is causing the pH to drop I'm sure is having an easier time doing so because of the low Alk but I don't think the Alk itself is responsible for the drop. I am testing after each 2lbs of BS.

PatL34
06-01-2006, 04:51 PM
Changes in pool chemistry can take time Wayne, so be patient. The low Alk is definitely responsible for the continuing drop, and as you increase it you will be able to control the pH more easily. Testing the way you are doing is excellent.

Keep us posted as to what is happening.

Pat

Wayne LaBanca
06-02-2006, 06:19 AM
Changes in pool chemistry can take time Wayne, so be patient. The low Alk is definitely responsible for the continuing drop, and as you increase it you will be able to control the pH more easily. Testing the way you are doing is excellent.

Keep us posted as to what is happening.

Pat

Where getting there. I set myself back a bit, I had to top the pool off at lunch yesterday and forgot to turn it off when I left. Needless to say, I over filled it "slightly".

Anyway. pH is now 7.4 and alk is 70, it probably would have been higher if not for my fantastic memory. :) Interestingly, with the Cya as low as it is, 10-20, it's holding Cl fairly well. Full sun and hot yesterday and the Cl was still 3ppm in the evening from 6ppm in the morning.

The white haze is clearing, slowly. It has been 3 days running the pump 27/7. Should it take this long to clear?

aylad
06-02-2006, 06:44 AM
Hang in there, and keep the pump on. Ben's (Pooldoc's) position has always been that AG pool filters are notoriously undersized, so it tends to take longer to filter dead algae out of an AG pool than from an IG.

Janet

Wayne LaBanca
06-04-2006, 08:11 AM
OK,
pH seems to have settled in at 7.6 and I have the Alk to 110. As to the pump/filter being matched; I have a Hayward GM152 sand filter with a Haward UN series 1hp pump. Not sure if this is a good match or the filter good enough for a 12,000 gallon pool. It was all given to me last year.

Still hazy but getting better...

Wayne