Newbie - Stain removal via ascorbic acid

[Watermom]

Good to hear there is progress! Thanks for the update.

[herb396]

Ok as of 10:00 am this morning it looks like we are stain free. Some light areas that seem to go away with some brushing, so a good bruising all around will be today's task. Water is clearing up, can now see the drain in the deep end, but it's not crystal clear (yet).

CL is about 1.5 -(I say "about" because the little test kit w/drops & you match the colors. It matches the 1-2 mark) But I've been able to hold that level most of the week.

pH is about 7.0 - I added another two quarts of muriatic acid after taking that reading.

Been laying off the polyquat because prior to all this we doused the pool with about three bottles of the hTh algaecide (thinking the stain might have been algae). The water still has an odor to it and it foams up a bit when splashed around.

So what's my next move? Do I start thinking about bringing my levels back up & chlorinating using calcium hypochlorite granular chlorine? Or should I hold these levels for a while longer?

herb

[aylad]

Definitely don't add any more of the HTH algaecide--the chlorine you use will eventually break down whatever's causing the smell and the foaming. Remember that algaecides are much better at preventing an algae outbreak than they are at killing an active one--and even then you only want to use Polyquat 60 because of the same problems that you mentioned.

I'll let one of the stain experts advise you on whether it's time to start raising your levels again, but I just wanted to warn you that when you do, do it slowly so that if you start to see browning of your water you can get some sequestrant in there before you end up with staining again. High chlorine and high pH levels are what bring the metals out of solution, so just have that in mind when you start raising your levels.

Janet

[herb396]

Holding the current levels for the past few days:
CL: 1.5
pH - 6.8

Water is gradually clearing up, not milky, just cloudy at this point, but I can see the bottom of the deep end pretty well. Satin in mostly gone, there is a light band about 8" wide just below the water line on about half the pool, but the walls and bottom are clear. No change in stain lift for the past two days now, so I would guess it's probably as far as it going to go.

So my question lies in when do I begin to start thinking about bringing my levels back up & chlorinating using calcium hypochlorite granular chlorine.

thanks,
herb

[aylad]

I don't think I'd use cal-hypo at all--your hardness is already at 250, and it won't be long before the excess calcium will cloud up your water. I'd go with straight bleach or liquid chlorine. I don't see any reason why you can't start bringing up your chlorine levels now, just do it slowly keeping an eye out for water color changes.

Janet

[herb396]

Janet,
I mentioned the chlorinating using calcium hypochlorite granular chlorine because it was what Ben's initial directions gave me when giving he help develop a plan to address the stain.

But if the calcium is going to be an issue,,,then obviously I just want to do the right thing.

[aylad]

I just went back and re-read the whole thread and realized that you have a plaster pool, not a vinyl one. In that case, cal-hypo is fine, because your target CH in a plaster pool should be 200-400 anyway. My mistake, sorry!!

In a plaster pool, calcium is a much bigger issue if it's low than if it's high, because if the water doesn't contain enough calcium, it will leach it from the plaster, making it brittle.

So you're right, Ben's right (of course), and I'll slink out of this now.....

Janet

[waterbear]

Janet,
I mentioned the chlorinating using calcium hypochlorite granular chlorine because it was what Ben's initial directions gave me when giving he help develop a plan to address the stain.

But if the calcium is going to be an issue,,,then obviously I just want to do the right thing.

I would follow Ben's directions. In fact, in this newsletter he talks about shocking with cal hypo in the skimmer
http://www.poolforum.com/pf2/showthread.php?t=10246
and he gives much fuller directiosn here:
http://www.poolforum.com/pf2/showthread.php?t=10217
He suggests that by using cal hypo this way excess calcium precipitates out in the filter and acts as a 'filter aid'. Worth trying but do keep tabs on your
CH and if it climbs beyond reasonable levels switch back to bleach.