Use Of Metal X

[JimKW]

I bought a used Sundance Optima 1.5 years ago. The guy who had it before me always put 8 oz of Metal X in it when he changed the water and then would add 1 oz every week when he shocked it. I use the same Chlorine/Dichlor as he did and kept putting the Metal X in also. I now watch the CYA and when it hits 30-50 I switch to regular bleach instead of the dichlor.

On my last fill (past Saturday) I was out of Metal X so I didn't add any. I find that my pool is not experiencing the intitial chlorine use that it normally does when I first fill it. Usually I have to keep adding chlorine for about 10 days before it starts holding the level up. This time I put 2.5 oz in on initial start up and 1 oz the next day just because I assumed it would need it, but did not honestly check. The next day when I checked it was at 17, following day 14 and the next day around 10. So for four days I have not added any chlorine.

Sure sounds like the Metal X was causing it to use chlorine doesn't it? But should I still be using it anyway? I have the Taylor test kit and have all my levels pretty much right on.

Thanks, Jim

[chem geek]

Is the product you are using Robarb Metal-X? If so, then as indicated in this MSDS, the product is the metal sequestrant EDTA. This metal sequestrant tends to break down from chlorine which explains the higher chlorine demand after you use it. Better metal sequestrants use HEDP which is more resistant to breakdown from chlorine. However, unless you know you have metals in your water, you shouldn't need a metal sequestrant at all.

[JimKW]

How do I check for metals in my water? I don't think I do, but not sure.

[chem geek]

There are expensive metal test kits such as the Taylor K-1264 that tests for iron and copper or the Taylor K-1716 that tests for iron only, but this is one time where pool stores can be useful for testing a water sample for metals. Unless you are on well water, it is not likely that you have metals in your water. If you have a water quality report from your water district, then that's probably the easiest and most accurate way to know what is in your water.

[JimKW]

I can hardly believe how little Chlorine I am now using. Like I said when I just assumed I would need as much as I did with previous refills the level jumped to 17. It came down to 14 then to 10. We have used the tub very little and the level was still at 4 a week later. On Sunday I added about 3/4 oz of Chlorine with Dichlor. If I had put the Metal X in I would have already started using Bleach after pooring in about 6 oz of Chlorine with Dichlor. My CYA was still a little under 30 and my Chlorine level was about 3 when I put in 3/4 oz.