High Nitrates

[cwahoo]

Just had my water tested. They said I had high nitrates due to fertilizing my lawn. I don't believe this is possible. They said to drain my pool or to add 7lbs of Shock and retest in 24 hours. Any other solutions? Is shocking my pool going to fix the problem.

My free chlorine level was .6.

Thanks for the help.

 

[dschlic1]

Chlorine will "burn" up nitrates. Until all nitrates have been removed, you will not be able to maintain a normal FC level.

 

[Melt In The Sun]

Welcome to TFP!
Chlorine will do nothing to nitrates, and you don't need to drain your pool because of them. They are algae food, but as long as you keep a high enough FC level, they are of no concern.

When you have a few minutes, take a read through Pool School (button in the upper right corner of the page). You'll learn everything you need to know to never have a problem with your water again. Really!

 

[RobbieH]

Do you have your TC or CC numbers?

Gotta love pool stores.

 

[cwahoo]

I do have CC numbers but very low FC levels. How do I keep the FC levels high enough. Water is clear, but has a greenish tint.

 

[RobbieH]

Can you post your CC number? CC of over .5 and a greenish tint most likely means you need to follow the shock process. Please don't just add a bag of shock, follow the proper shock process on Pool School.
pool-school/shocking_your_pool

 

[cwahoo]

Total Chlorine is 1.6 and the FC level is .6.

 

[Bama Rambler]

So your CC level is 1 ppm. See Robbie's post above ^^ !

 

[cwahoo]

So just had water retested at another pool company~
Once again told to drain pool. Here are the readings

FC- .3
TC- 2.9
CC- 2.6
PH- 8.0
Alkalinity- 94 ppm
phosphate -2500 ppb
Nitrates- 34 ppm

If I shock the pool, is that going to correct the problem or is the only way to drain pool?
Using the chart (CYA) one I find my FC Shock #, what does that number mean?
Thanks for all the help. I would really like to find a solution that does not require me to drain.

 

[duraleigh]

I would really like to find a solution that does not require me to drain.

You have found one in the posts above... Shock the pool.

If you do it ANY other way than as prescribed in Pool School, you will probably not get your pool clear.

 

[JasonLion]

Shocking will take care of it. Nitrates are not the problem here. The issue with fertilizer is ammonia, which can take fairly large amounts of chlorine to "burn off". Depending on just how much fertilizer got in the pool there is a small chance that draining and refilling will be more efficient, but it is rather unlikely, and certainly not required.

 

[cwahoo]

JasonLion,
So how much shock would you suggest? The pool is 18x36. About 26,000 gallons.

 

[JasonLion]

It uses as much as it uses. You follow the usual shock process (add chlorine, wait an hour, test, repeat), except use the mustard algae shock level instead of regular shock level.

There is a way to estimate just how much chlorine you will need in total, but it is somewhat involved, see this post, but doing that is not required.

 

[cwahoo]

Jason, Thanks. Since I don't have liquid chlorine or bleach on hand and I would like to get the process started this evening, Will adding pool shock (68% calcium hypochlorite / 32% other) get me started in the right direction? I'm estimating 4-5 16 oz bags to start with our 26000 gallon pool. Sound ok?

 

[JasonLion]

Cal-hypo is fine, especially for limited use, as long as your CH level isn't already too high. It is unlikely you will want to continue using cal-hypo (though get a CH test to find out), but using it at first should be fine.

 

[cwahoo]

I am trying to find and buy liquid chlorine. The pools stores and hardware stores don't carry it here. Any ideas of where to buy it?

 

[RobbieH]

Go to your grocery store, look for the bottles that say Clorox on them.

You can use store brand bleach too, but make sure to read the label, if it doesn't say 6%, keep looking.

Don't buy anything scented or extra this or that, just plain bleach.