Low pH and High Alkalinity

Problems relating to pH and total alkalinity.
Increase ph, increase TA. Reduce pH, reduce TA.
pH chemistry advice and techniques for the pool.
california
Pool Newbie
Pool Newbie
Posts: 7
Joined: Fri 01 Oct, 2010 16:31
My Pool: inground kinda square with attached jaccuzzi
21000 gal built in the 1960's
DE filter
Location: So Cal

Low pH and High Alkalinity

Postby california » Wed 06 Oct, 2010 15:54

I am sure y'all have been itchin' to find out what happened. I pumped and dumped the water. Refilled from the tap. Alkalinity from the city water looks to be 120 and my pool is about that as well. My pool now has a respectable level of 30ppm CYA and a pH of 7.4. I bumped the CL to 5ppm (to give the remaining algea an unpleasant environment) and it seems to be holding right there for both free and total. It took relativly little Cl compared to what I previously had to put in. I put in 182 oz. of bleach, 1 gal of 10% pool Cl and I've got a couple of floaters of trichlor tabs.

I would never have figured this out without finding a great source of information like you have here on this board. Thanks to all the contributors. You schooled me and I am happy. :thumbup:


Allen G Myerson

Low pH and High Alkalinity

Postby Allen G Myerson » Wed 06 Oct, 2010 18:51

Thanks for the update. It really helps to know how a post turned out. Be sure to keep your Cyanuric acid between 30 and 60 ppm and keep your FC at 7.5 % of the Cyanuric acid. Maintain your CSI between 0.0 and +0.3. Also, you should get the Taylor K-2006 test kit if you don't already have it.

Use the pool calculator to calculate chemical dosages and to calculate your CSI.
CA

Low pH and High Alkalinity

Postby CA » Sun 17 Jun, 2012 16:49

Why is almost everyone saying to add acid until the PH and Alkalinity comes down when the problem and the title of the article is that the PH is too LOW and the Alkalinity too high?
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Low pH and High Alkalinity

Postby chem geek » Sun 17 Jun, 2012 18:51

Because the original poster's issue was interspersed with other posters that had different problems. If you go to the first page and read the original responses, they dealt with being able to raise the pH with less of a rise in TA, such as by using 20 Mule Team Borax. They also mention how aeration can raise the pH with no change in TA. It is later posts where people reported high TA but not low pH and for them adding acid with aeration all done at a lower pH (usually around 7.0) is how you lower the TA.
shell38

Low pH and High Alkalinity

Postby shell38 » Thu 27 Jun, 2013 08:32

I have been fighting with a green pool for a week now... I have been adding the HTH minus every 24 hours... Vaccumed.. changed filters.... The debree was on the pool floor... Not its on top .... Ph was normal... Alkalinity high.. we have had rain for the past 3 days. Today I tested it... Ph high as well is alkalinity added HTH minus about 3 hours ago. Do I just let the pump keep working or add pool shock??? HELP!!!,
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Low pH and High Alkalinity

Postby chem geek » Thu 27 Jun, 2013 13:45

Mattgrae84
Pool Newbie
Pool Newbie
Posts: 2
Joined: Tue 27 May, 2014 21:56
My Pool: -tiled 50m pool 1.5 million litres
LTs pool 105000L pebble surface
Free form pool: 300000L pebble surface.
Location: cairns

Low pH and High Alkalinity

Postby Mattgrae84 » Tue 27 May, 2014 22:13

i have a covered pebble pool that is 105,000litres. using liquid cholrine. i am getting free cholrine test results at about 2.5, Ph is at 7.2 Alkalinity is at 330mg/L. i have tried bring down the Alkalinity using acid but just goes up again. It came down to 110mg/l then went back up again after a couple of days. should i keep doing this or is there a different solutions. thanks

Return to “pH & Total Alkalinity”

Who is online at the Pool Help Forum

Users browsing this forum: No registered users and 0 guests