Light brown stains from pool need suggestions

[SunnyOptimism]

Tested today at 4/20/2015

FC is 50 drops x 3 - 150 ( too high)
CC - 5 Drops
PH - 10 drops (Base Demand Test)
TA - 90
Calcium Hardness - 300
2 weeks ago when opening I added CYA of about 3 LBS remainder accidentally. I do not have the CYA agent to test....for now.
What I should do? Thanks

[EDIT]

DUH!! Just realized something - if your FC is so high (which it could be), then your pH tests are all meaningless!! FC over 10ppm causes the phenol red indicator dye to chemically change giving it false color readings.

SO, you need to get below 10ppm FC to do any other tests. The CH and TA indicator dyes are also chemically interfered with by high FC.

[END-EDIT]



Is it 50drops or 150drops? Why are you multiplying by 3??

If your water sample size is 25mL and its 50 drops then -

FC = 10ppm
CC = 1ppm

pH - ??? (It's 5 drops of phenol red and then compare color of solution to color comparator on measurement block...why were you putting in Base Demand??)

TA = 90ppm
CH = 300ppm

If your sample size was 10mL and it's 50drops then -

FC = 25ppm
CC = 2.5ppm

So, either way your water is not right. You have 1ppm at least of CC's which is indicative of organic waste in your water.

You have to get your CYA tested. Order more reagent. Try Amazon. As a stop-gap measure you could take a water sample to a pool store and ask for them to test your stabilizer level. Pool stores suck at testing CYA and usually get it wrong, but you have no CYA reagent test and it's going to take time.

Assuming you were actually at 0ppm CYA, then adding 3lbs of stabilizer would get you to 17ppm. You would have needed to add 84oz (5lbs 4oz) to go from 0ppm to 30ppm. So, you're not even halfway there yet...again, ASSUMING your CYA was actually 0ppm.

At this point you need to retest pH and report back as adding that much base demand reagent makes no sense. Whatever your pH is, it needs to be ~7.2 or so in order to shock your pool.

One question - how old is your K-2006 test kit? None of these numbers/drop counts make any sense. If your reagents are old or spent time outside the house in a cold/hot/humid environment, your reagents could be screwed up. Several of them are temperature and humidity sensitive.

I'll ask others to chime in, but until you can get your testing under control, you may have to go to a pool store and get your water tested there. It's a lousy option but the only one that make sense to me given all the spurious test results.

[SunnyOptimism]

After pondering it a bit more, I think the prudent course of action is to not do or add anything and let your FC fall back into a normal range (less than 10ppm). Until we can accurately test water values, we'll just be chasing our tails.

Also, the CYA test can be interfered with by high FC levels and cold water temperature. The water sample for CYA needs to be below 10ppm FC and at ~70F for an accurate read.

Can you order more CYA reagent?

Forget pool store testing too, the high FC will screw them up as well

[SunnyOptimism]

One other trick you can try to get a pH reading - take a sample of pool water and dilute it with equal parts of DISTILLED water (not bottled spring water or tap water). You can typically buy DISTILLED water in a supermarket as it is used in steam irons and coffee pots.

It turns out that DISTILLED water has a pH of 7.0 And practically 0ppm TA. Therefore, mixing it with pool water will not change the pH due to the buffering capability of the pool water (the pool water sample resists pH changes because it had a much higher TA than the DISTILLED water).

If you do this, you should be able to get a better read of your pH.

[FormerBromineUser]

How is it going?

[phillipjko]

Ok, let's go through this slowly.

First off, stop listening to your neighbor. Rain water has no metals in it (where would the metals come from??). Rain water is actually a good thing in your case because it is pure water and if you let it fill your pool (while removing old water) then you can naturally reduce your metal levels. But for now, forget about metals as your water quality is more important at the moment.

@FBU is correct, your pH is waaaaaaay too low. Borax is one way to raise it but you have very low TA so, if you can find it, you can use washing soda (sodium carbonate....NOT BAKING SODA which is sodium bicarbonate). Pure sodium carbonate is not easy to find in the stores, but sometimes you get lucky. Pool stores sell it but at a major price markup. Borax (20 Mule Team) will raise pH without raising alkalinity but you shouldn't have more than 50ppm of borates in your water and I don't want you to create one problem trying fix another.

@FBU is also right in that I don't understand your chlorine numbers. I need to know free chlorine (FC) and combined chloramines (CC). Please retest those and report. If your CC's are high then your water is definitely NOT OK. You can have clear water and high CCs which is typically indicative of a nascent algae bloom.

I see you have an SWG. How old is it? The Cu you have in your water could be coming from old or damaged plates in the SWG. With your pH so low, you could have easily damaged the coating on the SWG plates and exposed the Cu metal underneath. But for right now, you are not going to run the SWG. You should do all of your chlorination manually using liquid chlorine (bleach) until we get your pool water under control.

How confident are you with that CYA test? CYA of 0 is unusual but not unheard of in winterized pools. Certain types of Bacteria and algae can consume CYA during the winter and produce ammonia. Sometimes a 0 reading is caused by operator error during the test OR because your other water values are so far off that the CYA test is not accurate (especially with your pH being so acidic).

Which leads me to another question - how did you get those pH values? The K-2006 kit uses phenol red indicator which doesn't show color changes below 6.8 and certain can't read down to 5.4.

Please respond with the following water parameters using the K-2006 :

FC
CC
TA
pH
CYA
CH (this one is not very important to get right at the moment).

DO NOT ADD ANY CYA UNTIL YOU GET A FULL SET OF RESULTS. If your CYA test is off and you do have CYA in the water, you do not want to overshoot as the only way to lower CYA is by draining.

Currently the following values are


FC 50
CC 0
TA 120
pH 7.2
CYA 20
CH 300
copper 0.2

Water is now clear.. but the stains are kinda coming back strangely. Under direct sunlight they look fine

https://www.flickr.com/photos/128250...posted-public/
https://www.flickr.com/photos/128250...posted-public/

but under shade there are browning maybe one would call copper stains.

[phillipjko]

Thanks so much for the advise. It was good. I got it all balance finally. I know.. there is still copper but somehow the brown stains are coming back on the steps and liner... see my photo below... that was a few days ago.

[SunnyOptimism]

Currently the following values are


FC 50
CC 0
TA 120
pH 7.2
CYA 20
CH 300
copper 0.2

Water is now clear.. but the stains are kinda coming back strangely. Under direct sunlight they look fine

https://www.flickr.com/photos/128250...posted-public/
https://www.flickr.com/photos/128250...posted-public/

but under shade there are browning maybe one would call copper stains.

I'm still confused by that FC number. Is it 50ppm or drops? If drops, then what samples size did you used, 10mL or 25mL?

There's a way you can determine what the stain is. You'll need a 3" trichlor tablet and a high concentration Vitamin C tablet. You put the trichlor tablet on the stain and if the stain lightens or disappears, then it is likely algae. If the trichlor tablet doesn't get rid of the stain, then try the Vitamin C tablet. If it lightens or disappears with application of the Vitamin C tablet then it is likely a metal (Cu or Fe). DO NOT LEAVE THE TABLET ON FOR A LONG PERIOD OF TIME AS THEY CAN ETCH A PLASTER SURFACE AND FADE VINYL.

If the stains are metals, then we'll have to run through an ascorbic acid treatment process.