My Beautiful Chlorine Monster! Help!

NHPool

Member
Jun 22, 2010
5
New Hampshire
New to the site and really appreciate it. Thanks!

pH - 7.5
TA - 110
FC - 7 (but falling fast)
CC - 0
CH - 100
CYA - 80

Pool is amazingly crystal clear but it is gobbling chlorine...about 15 ppm per day (including 5ppm at night per the FC night test)

I've been busy (too busy perhaps) the past few days
1] added 45 pounds baking soda (all at once) to get TA to 150 per pool store recommendation (before finding this site)…pool turned green for a couple days
2] stains appeared all over the pool, which I diagnosed as metal stains with Vitamin C tablets (metal stains presumably caused by huge pH/TA swing from all that baking soda all at once)?
3] removed the stains with 10 pounds citric acid and 2 pounds ascorbic acid…prepping the pool with 3 pounds chlorine neutralizer and some muriatic acid to lower pH to maximize impact….this made the pool look amazingly good
4] added 1.5 quarts sequestering agent
4] received my TF-100 test kit
5] brought pH back up with 3 boxes Borax
6] added 6 more boxes Borax (and a gallon muriatic acid) to get Borate level partially up
7] drained 25% of the pool to help bring TA and CYA down…replacing water with my well water (TA=120, pH 7.5)
8] reduced TA with muriatic acid (2 gallons) and aeration

The GOOD
- My numbers are under control (but I'd like to get CYA down even further)….everything above seems to be working.
- The pool is beautiful (moreso than ever…)

The BAD
- The pool is consuming chlorine at a scary rate. Major Chlorine Demand issue.

What could be causing the very very high chlorine demand?
- well water (nitrates? Phosphates?)
- phosphates (from sequestering agent)
- chlorine still working on all that citric/ascorbic acid
- chlorine still working on all that neutralizer
- muriatic acid?

I am puzzled that I keep getting the CC=0 reading.

I read that I may be able to "shock my way out of this" but I haven't shocked yet since the post for the ascorbic acid treatment said I can't shock for 2 weeks.

My current plan is to just keep "feeding the beast" 3 gallons of 12% liquid chlorine every day and hope that this issue resolves. If it doesn't, then I plan to shock the heck out of the pool, per the shock value on the CYA table.

What else should I be looking for or trying?
 

ssa

LifeTime Supporter
May 24, 2010
26
San Jose,CA
Most likely it is just algae or other organic matters.

You need to shock your pool. But before that, you'd better get the CYA level further down.
CYA 80 is still too high. You are looking at chlorine level of 30+ppm for shocking.

Do you know your local water source has high metal or not? If not, replacing water
can bring both CYA and metal source down.
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,293
East Texas
If it is algae, wouldn't the CC register a bunch more than 0.0? I'm still learning here. Or does algae even show up as CC?
 

bk406

Well-known member
Dec 3, 2009
2,690
Central Massachusetts
My bet is that you dont have algea. The chlorine is most likely getting chewed up by all the ascorbic and citric acid you added, as well as maybe some residual chlorine neutralizer.

The reason the directions say dont shock for 2 weeks is that high chlorine so soon after the ascorbic acid treatment can precipiate metals back out. I beleive the only way you will lessen the chlorine demand is to keep adding it until the ascorbic/citric acid has been depleted.
 

ssa

LifeTime Supporter
May 24, 2010
26
San Jose,CA
woodyp said:
If it is algae, wouldn't the CC register a bunch more than 0.0? I'm still learning here. Or does algae even show up as CC?
Good question. I don't know the answer to that. I am not very familiar with the
other metal removing chemical, but I suspect it does not actually remove the metal.
It just prevent it show up as stain.

Algae itself does not show up as CC. The chlorine get used up to
kill Algae show up as CC.
 

ssa

LifeTime Supporter
May 24, 2010
26
San Jose,CA
bk406 said:
The reason the directions say dont shock for 2 weeks is that high chlorine so soon after the ascorbic acid treatment can precipiate metals back out. I beleive the only way you will lessen the chlorine demand is to keep adding it until the ascorbic/citric acid has been depleted.
If the ascorbic/citric acid depleted, will the metal stain show up again?