Ascorbic Acid Treatment

[Watermom]

I like around 40. What is it your level currently?

[Chrissymok]

currently it is 99...that's why we need to get it down

[mbar]

Anywhere between 30 - 50ppms

[Chrissymok]

After draining 1/3 of the pool and refilling (twice!) we still only got the cya level down to 76. With the FC down to 0 we used a stain out product and then a metal out product. The pool looked great...until we added chlorine back in...now all surfaces are stained again. This is the 2nd time we have done this whole process and while the copper has gone down from .4 to .1 we still can't seem to get it out. The stain out and metal out are pretty expensive and we don't want to keep having to use them. Our public water has no copper in it...we think it must have come from algecide that the pool openers used. How can we get better results that will last? Can we ever totally remove the copper...or will we eventually have to drain the entire pool? We feel like we are going to be battling this forever and we don't want to keep throwing $90+ away everytime we try to treat the problem. Any advice would be appreciated, thanks!!!

-16,000 gallon inground pool, with vinyl liner & sand filter

[pilot-werx]

I was in the same boat as you and have tried just about everything... My CYA is higher than yours (100) and here is what I have done with the best results. (Dumping water was not an option)

If your water is clear, stop feeding chlorine and let the levels come down to 1 ppm or so. For your amount of water, get about 2 lbs of ascorbic acid and two bottles of ProTeam Metal Magic. When the chlorine drops, bring the pH up to around 7.6-7.8. With the pH correct, add the ascorbic acid it the skimmer. Let the acid circulate for a couple of hours or until the stains have disappeared. When the stains are gone, add two bottles of Metal Magic. Wait 24 hours and then start to bring the chlorine up. Do not add any shock or liquid chlorine. If you have a feeder, put it on its lowest setting. If you put tabs in the skimmer, just keep an eye on your chlorine levels. You do not want to go higher than 2-3 ppm. If you have high metals, every week, you will need to add metal magic.

I have been fighting this all summer and so far this has been the best. The ascorbic is expensive but the Metal Magic is $17 at my local store. I feel somewhat stupid because I am a water engineer and this has been the hardest thing to deal with.

Give it a try and let me know how it goes.

Regards,
Chris

[mbar]

Hi Chris, you have it about right. The most important thing is to never let the chlorine get too low or you risk an algae breakout then you have to shock.

Chrissymok, I feel your pain. This is what I would try before doing the whole ascorbic treatment again. Lower the ph to 7.0-7.2, add more sequestering agent proteams metal magic is my choice also. Keep your chlorine at the lower end of the "best guess chart" for a while. The new stains should disappear without the ascorbic acid. If the stains are still there after a day or so, then add a small amount of ascorbic at a time, letting the water circulate between additions until the stain is gone. Add more sequestering agent if you see stains start to appear when your chlorine level is back to normal. Remember high chlorine along with high ph is what makes the metals fall out of solution. As for where your metals are coming from, it is hard to say. If it is from something you added, it should go away with time as your water is replaced.