My first brown water

[Phenom300]

I opened my pool last weekend and proceeded to turn my nice blue water into a brown mess when I added my Walmart bleach. I have never had this trouble before when I topped off the water from my well, but I know it’s always a risk when using well water. I ran my sand filter that contains ZeoBright and threw some clean white shop towels into the pool to give the iron a place to go and after 24 hours my brown water was gone. I was however left with a shiny clear green water. During the process I backwashed the filter every 2 hours and I was surprised at how much coffee colored water came out each time. I also rung out the towels and placed them back into the water. My point to this is that I was clearly removing the iron from my water; the proof was in the backwash. Late yesterday afternoon I added 64 oz of HTH Metal Control from Walmart which shows its active ingredient as Hydroxyethylidene Diphosphonic Acid. Within two hours, my water was back to crystal blue. My question is this, I realize that these chemicals do not remove the iron, my filter and towels were doing that as evidenced by the backwash and rusty towels. Am I still removing iron from my water now that I can’t see it?

I don’t have the numbers from a water test as my Taylor kit is scheduled to arrive this week. My Walmart kit shows my CL at a near nuclear level (I over did the shocking) and my Ph is around 7.4.

Thanks.

[aylad]

The metal control is designed to keep the metals in suspension in the water so that they do not drop out onto filters, liners, etc. so you're not removing anything at this time, unless the chlorine has broken down the Metal Control that you put in.

Clear green water sounds like copper. Have you added any copper to the water (dual action trichlor pucks, copper algaecides, etc), or does your well water also contain copper?

[PoolDoc]

Actually, Janet, in my experience, clear green is soluble iron. Copper can be a bluish green, but usually the coloration is not strong enough to be distinct.

Phenom, using HEDP (that's the short name for the chemical) will keep the soluble iron in a very soluble state . . . but only temporarily. However, it's difficult to REMOVE the iron, while it's chelated by the HEDP. There are four ways to actually REMOVE the iron that I know of:

1. You can trap it on the filter, in a state that can be removed. You'll have to clean your filter regularly, to accomplish this -- if you trap it, and then leave it, you'll tend to keep redissolving some of it. If you happen to have access to solid pieces of calcium hypochlorite -- like Pulsar tabs -- keeping one or two of those in your skimmer will definitely help.

2. You can use alum or polyaluminum chloride to trap it, and then settle it to the bottom OR catch it on the filter.

3. You can do a high pH lime softening precipitation of the iron, using washing soda to push your pH very high, temporarily, and settling the iron as ferric hydroxide.

4. You can use the "CuLater" patented zeolite-like product. We're not 100% sure this works, but we think it does. AND, it's the only method that will possibly remove the iron while it's still chelated by the HEPD.

Right now, you should be OK. The HEDP will last at least a week or so, unless you push the chlorine very high. So think about it and post your test results when you get the K2006. I'll edit this post of mine, to add Amazon links to some of the products, you might use, so you can look at those.

[Phenom300]

Thanks for the quick reply. So was I infact removing iron with my filter while the water was brown and green? If so, is it not better to delay adding the HEDP so my filter has more time to remove the iron? I didnt need to rush to get clear blue water as it's still rather chilly outside here in Ohio.

[PoolDoc]

Removing metals from pool water without leaving stains behind is not a problem we've fully solved here. So, the truth is, I don't know if it would have been better to keep filtering, or to add the HEDP, and finish removing later. Having the HEDP in the water can lift recent stains back into the water. So . . . it may well have been better to add the HEDP.

Hopefully in 2015 we'll have a clear and complete program for managing metals in pools. But this summer, we're going to be experimenting to find the best way(s).

I've started a collection of all the pool chemicals out there -- well, MSDS, sales, and label sheets -- so we can ID specific chemicals hiding behind brand names. (Over 8 GBytes of files, so far!) That's a first step to helping people. As long as the products are mystery products, we can't apply a systematic approach to the chemistry.

[Phenom300]

I got my Taylor 2006 today and here are my numbers

ALK 170
PH 7.0
CH 80
CYA 55
FC 21
CC 0
TC 21

I knew my TC would be high because I nuked it which caused my brown problem to begin with. I have added some muratic acid over the last few days to lower my ALK, I am currently aerating to raise my PH. Is it ok that I have 0 CC?

My water is crystal clear but I still am backwashing rusty water into the yard.

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I was doing the chlorine test wrong. My FC is 9.0 and my CC is 0.5. The rest of the above numbers are the same.