High cya .... Need advice

[Goodtwin]

I have 15 round above ground w/ vinyl
About 5000 gallons
Filter is D.E.
No heater

FC 0.4 ppm
TC 2.52ppm
CC 2.12 ppm
PH 7.6
Hardness 164 ppm
Alkalinty 121 ppm
Copper 0.3
Iron 0.1
PHOSPHATE .... Way over at 2282 ppb

Last the cya read was....
113 ppm

As a result I have a purple sand like substance settled at the bottom of the pool.
It brushes away easily

The water is clear

Is there any other way to solve this besides draining the pool? Just trying to figure out the best way to fix this eye sore

In which order should I tackle these issues?

Thank u for ur time

 

[YippeeSkippy]

Welcome to TFP! Glad to have you here

You know your CYA is too high but those appear to be pool store tests. Pool store tests are hit and miss for accuracy. More often than not, misses.
Your FC is too low and you have something growing in the water based on your CCs. When your CYA is so high it requires higher and higher FC levels to be effective. I would suggest first getting your own test kit (TF-100 is the *bomb.com* of test kits, link in siggy line) and learn to test yourself.

Ignore phosphates as they are meaningless when you keep your pool properly sanitized with chlorine. And by chlorine I mean either liquid chlorine (aka "bleach" which is 8.25%, or pool liquid chlorine which is higher % but neither have ANY other ingredient in them to mess with your water) or via a Salt Water Generator (SWG) which produces its own chlorine from salt you add to your water. Don't use pucks or granular chlorine, they contain either CYA or calcium and cause the build up problems.

You're going to need to drain some water and replace to get that CYA down. Pool Math application can help you.

Read up on pool care- start here: ABCs of Pool Water Chemistry

Holler back with any questions

Yip

 

[pooldv]

Welcome to TFP!

 

[Goodtwin]

Ok so let me make sure I am understanding you correctly.... 1st I should lower the cya because it is making my chlorine dosage ineffective because due to the high cya it wants MORRREE lol....once my cya is in range I should chlorinate using liquid chlorine.... will this help get rid of the purple stuff at the bottom? Should vacuum to waste? Kill two birds w one stone? Would a shock treatment be a waste of time?

 

[Mr Bruce]

The first order of business is a proper test kit. Pool store testing is usually terrible. I recommend the TF100. There is a link in my signature.

Welcome!

 

[pooldv]

Chlorine level is set based on the CYA level and the [FC/CYA][/FC/CYA]. FC must always be kept above minimum to keep the pool sanitary and prevent algae from growing. FC must be brought to shock level to kill algae following this process, SLAM Process.

It is all covered in Pool School
start here, ABCs of Pool Water Chemistry
then here, Pool School - Getting Started

Add your pool info to your signature so that we can better help you. There are different rules about draining pools depending on what you have. More here, Pool School - Read This Before You Post

 

[Goodtwin]

But wouldn't I have to lower the cya first before slamming? Otherwise the shock treatment would be ineffective?

 

[triptyx]

If the pool store's CYA reading is correct, then yes, you want to drain/refill water to lower the CYA prior to starting a SLAM. You'll require far less chlorine to reach SLAM levels. That said, the first thing we need is for you to get one of the recommended test kits so that we can get the real numbers for your pool and give you the correct advice for your pool.

 

[paulmaz]

Goodtwin,

My advice here...being new myself here...is if you really want to get good advice from the pros on this board, you need to convince them that you are ready to follow the ways of TFP. First and foremost, means getting your own test kit and test the water yourself. Nobody on here is going to recommend anything to you until you test yourself. They will not even look at your pool store results, as they are unreliable.

Once you ordered the test kit, while you are waiting for it, they can recommend steps to take until you post your first test result set. Then they can nail down your issue(s)

Welcome and good luck!

 

[Goodtwin]

Ok used my new TF-100 kit

FC -1.5
CC -0
PH -7.2
CYA -100
Alk-130

Again my pool info is
I have 15 round above ground w/ vinyl
About 5000 gallons
Filter is D.E.
No heater

The issue is clear water but the presence of purple sand like substance on the bottom of pool and a hint on the walls.

I did a vacuum to waste yesterday to get rid of some water and purple stuff. Got rid of most of the purple stuff but must have missed some because it is so fine.

The filter also went through a good cleaning and backwash.

I'm assuming my next step would be draining some water again to lower cya then a SLAM?

What should I use to chlorinate in the mean time?

Thanks again

 

[Cmasty]

Have you tried the dilution method to see what your CYA really is? With the reading at 100, you may very well be sitting at a much higher actual level. Mix pool water and tap water 50/50 and then perform the CYA test and multiply the result x 2.

 

[YippeeSkippy]

Bleach!!!! You need to get some bleach in to that pool PRONTO or you are inviting algae to take over. Your CCs are 0 now, but they might not stay that for long if you get algae.

I would add 1/2 jug of bleach daily until you get it all figured out with your CYA. You may need to drain and replace some water if your CYA is so high. BLEACH IS YOUR FRIEND!!

 

[Goodtwin]

Ok tried the dilution test .... Maybe I did it wrong but filled the cya tube all the way to the top and could still see black dot

 

[YippeeSkippy]

Ok tried the dilution test .... Maybe I did it wrong but filled the cya tube all the way to the top and could still see black dot

Ok, do another test with 3 parts tap water and 1 part pool water, using this mixture as your pool water and retest, multiply result by 4.

 

[Goodtwin]

Ok that's what I was thinking..... Just pour it evenly into the pool ? It stain liner correct?

- - - Updated - - -

It won't stain liner?

 

[triptyx]

Sorry, do you mean pour the bleach evenly into the pool? Or something else?

 

[Goodtwin]

Yea I never used bleach before so I'm just worried about staining the liner......what's your recommendation on pouring it in the pool?

 

[microscopes]

Yea I never used bleach before so I'm just worried about staining the liner......what's your recommendation on pouring it in the pool?

It stained my liner, but I don't care much.

 

[Cmasty]

Pour bleach slowly in front of a return jet.

Also, do the 4 part (3 parts tap, 1 part pool water) as YippeeSkippy said above. You may have to throw a ton of bleach at this thing if your CYA is as high as it sounds. If you can still see the dot at 1:1 ratio of tap to pool water, that means your CYA is 200+. While the more you dilute your CYA test, the error rate goes up, but it will give you a good notion/idea of what CYA ballpark you're in. Was the dot becoming obscured during the diluted CYA test?

 

[Goodtwin]

Barely became obscured..... I would say slightly cloudy