New pool questions

[tombomb]

We completed our new pool last August and having no knowledge of basics just did what the pool store said. We recently got stains and they gave us a quart of Metal Miracle on 4/15 and said it would take a few weeks to clear up the stains. I found this site and started reading it. We purchased a Leslies DPD test kit. Here are the results on 4/22:
Fc 5ppm
Tc 5ppm
Ph 7.4
Ta 150
Ch510
Cya 130
We added 1 gallon acid on 4/23 and 1gallon acid on 4/24 while aerating with a small fountain pump the whole time. Results on 4/25:
Fc 5
Tc 5
Ph 6.9
Ta 100
Ch 500
Cya 130
The fill water is well water and may have metal in it. I put some vitamin c on the stains but it didn’t dissolve. There was very little change. What should I do? Do I need to drain some water for the ch? How much would I need to drain to get it down? I read where a high cya on residential pool is not that bad just going to cause a little more chlorine use. I’ve ordered 5 lbs of ascorbic acid. Should I treat the stains before I drain the water or after? I really need advice on which problems are the most important and what order to deal with them. Any help would be greatly appreciated.

 

[jblizzle]

Welcome

First, you really need to have a FAS-DPD chlorine test so you know what your actual FC level is ... looks like what you have peaks out at 5ppm.

I am not to clear on dealing with metals, so will someone else comment on that. I do know that high FC levels can make the metal stains appear.

What made you drop the pH down below 7? That is generally not a good idea and can be pretty harsh on the plaster and pool equipment ... keep aerating to get that up ASAP ... might almost should add borax to get it up a bit.

There is not really a need to drain due to the CH, but a CYA of 130ppm (is that the max on your test because it very well could be higher) is going to be very difficult to maintain adequate levels of FC. For reference, at CYA of 130ppm, you would have to maintain FC > 10ppm to avoid algae issues ... can you currently test for that? What are you using to add chlorine?

I would recommend at least a 50% water change ... and possibly a second 50% water change after that to get you CYA in the 30-50ppm range.

Sorry I tend to ramble on

I would start by getting a FAS-DPD test kit and changing water to lower CYA and reading Pool School to further your understanding of what your pool needs.

 

[duraleigh]

It looks like you are aerating to reduce TA. Looks like it worked and you are low enough on TA to let your pH get back into the 7.'s, as Jason suggested. Perhaps it is temporary and you are3 agian aerating to bring it up but clear that point up for us.

The kit you got is fine except that it needs the FAS/DPD test as Jason says. That can be ordered separately from Taylor or TFTestkits when you get ready so you won't need a whole new kit.

Now...order of importance. If it were my pool, I would......

1. Plan on a 50% drain to lower the CYA down around to 50-60ppm or so.

2. Test your fill water for metals (and for CH) to see if that's an issue or not.

If the vitamin C didn't lighten or remove the stains, then it's unlikely they are metal so you will not need the ascorbic acid. Do you have any pool pucks? (tri-chlor) If you do or can get one, hold that on the stain for a few minutes to see if the stain lightens up or goes away. report the results back.

Once we get your post back, I think we can suggest an order of importance just a little better but let's see if we can find out what's in your fill water and what those stains are first. Can you post a pic of the stains?

 

[tombomb]

The acid and aerating was to try to lower the ta. I’m going to go get the fas/dpd test kit Saturday. I took the fill water and pool water to the pool store. The fill water has .20 copper and .28 iron. The pool water tested different than on my Leslie’s kit. I retested tonight. Here’s the comparison of
pool store my test:
FC 3.5 5
TC 3.5 5
PH 6.8 7
TA 0 100
CH 286 500
CYA 38 115 What would cause the difference? I have been using durachlor 3” tablets for chlorine. Here are some pics of the stains. Thanks for the help…

 

[duraleigh]

Take one issue at a time....

1. pool store testing...trust your testing and stay out of the pool store....that's why you bought your kit....the pool store test is bogus.

2. How and where did you get the testing for iron and copper? They are both too high....esp the copper. The iron is easy to understand but it's pretty unusual for copper to test in your well water. It's hard to be definitive from your pics but the test results and the pics suggest you have copper stains which are VERY difficult to get rid of.......an acid wash seems to be about the only way they are removed successfully based on reports here on the forum.

I would get the metal test done again from a different source and compare the two and then make some decisions if it tests positive again. Their pool water tests were off so the metal tests might need confirmation.