Newbie - Stain removal via ascorbic acid

[PoolDoc]

You should start GRADUALLY raising your chlorine level using cal hypo* added to the skimmer, to the 5 - 10 ppm range, while watching to see if stains reappear.

Meanwhile, continue to use polyquat regularly. Until your chlorine level is over 5 ppm, it won't be safe to depend on chlorine alone to keep your pool algae free.

PoolDoc

*All previous cautions about the dangers of doing this still apply. This is safe ONLY if you 'follow the rules'!

[herb396]

OK,,Things have been going great, the water is very close to being perfectly clear. I have been trying to gradually raise my CL level. I started last Thursday adding 1 cup every 12 hrs of cal hypo. I test every time prior to adding. First three days basically no change in the levels. (but I've stayed safe by adding the polyquat). Then bumped up the dosage by going 1-1/2 cup each time again every 12 hrs, level rose to .5. Yesterday I began to add 2 full scoops 3 x a day. last night my reading was still .5

In the morning I backwashed and then added 3 scoops. (It was 95 degrees here all week including today) I just tested and my CL level is now 10 ! , and the water is also a bit cloudy. I really tried to avoid this sudden rise. I might just be paranoid I think the steps are getting darker.

Should I add something to quickly lower the CL?

I wonder if there is something going on with the filter that would have released a bunch of cal hypo after backwashing?

[PoolDoc]

What is your stabilizer level?

If it's low, and you've been testing in the PM, but tested in the AM this time, you would expect results like that.

Full intense sun with clear water and low CYA can strip chlorine VERY rapidly.

Ben

[herb396]

Test results from pool store as of 10 am today:

Total Chlorine = 1.7
Free Chlorine = 1.7
CYA = 35
PH = 7.2
Total Alkalinity = 95
Adj. Total Alkalinity = 84
Copper = .5

Slight return of stain to steps and small area (10 x 15) in shallow area (near return ports)

[PoolDoc]

Yeah.

Low CYA with full sun will drop your chlorine a lot during the day.

Without a feeder, you probably need to take the CYA on up, so you can start the day with 6 ppm and end with 3 ppm.

Unfortunately, the reappearing stain is probably not really leaving in the first place -- it just changes form, depending on conditions in the pool.

PoolDoc

[herb396]

A week ago my CYA was 100. (where did it go and why?) I only have about 2-3 hrs of full sun.

Should I continue to chlorinate with the cal hypo (I have over 75lbs on hand) or should I return to the BBB method?

The reappearing stain is still dramatically less than when we began. (much more presentable) so were still very grateful to all the guidance.

Thanks

[PoolDoc]

OK, first I need to say the "BBB" method is an approach, not a set of chemicals. (It's my idea, so I get to say what it means! ) Bleach, borax and baking soda just happened to be what's available at the grocery store in generic form. "CHBB" is not as catchy, but if cal hypo were available at the grocery store, that page could have been titled "Cal hypo, borax, and baking soda".

Or, maybe not. My boys used to roll their eyes at me, while griping that I always alliterated at them, accidentally or not, when instructing them in life lessons.
-- Lisa, be nice! They really did! Now, they often alliterate, too, driving Susan nuts, since her alliterative achievements are almost always unimpressive. --

Seriously, BBB is not, fundamentally, about bleach. Bleach was just what was available.

Anyhow, your CYA hasn't disappeared. The only way it can do so is if you drain and refill, or if you have bacterial growth (equal major biofilms, AKA seriously slimy sidewalls*) that can biodegrade the CYA into urea and ammonia.

Most likely the difference is a testing discrepancy. Have test strips been used for any of your testing? I'm not sure if they've gotten better, but I know that when I tested several brands of test strips 4 or 5 years ago, the CYA test results were pretty hopeless.


Ben



* See, I just can't stop myself. Now, no doubt, there will be a new acronym: "Yes, you must have had a bad case of SSS over the winter -- that's why your CYA is missing".