Pool green after 2 weeks of hot + humid storms!

[Downfall]

About 30,000 gal. sand filter pool.

Shocked it twice over the past 2 days first with granular shock then I read I should use liquid so grabbed liquid shock and used that the 2nd time and earlier today I added metal out and algaecide but it didn't seem to help. I have had the filter running 24/7 and been brushing a lot which seemed to help a bit. I backwashed the filter a few times and got some green out the first few. I provided pictures of my test strip results I ordered a taylor kit but it will arrive in a week or so. It is around 90F and humid out now which probably doesn't help much. Any ideas?

 

[mknauss]

Welcome to the forum!
While you are waiting on your test kit, add 5 ppm FC worth of liquid chlorine / plain bleach to your pool each evening with the pump running. This will replenish the FC lost each day to the sun and also inhibit any algae in the water from growing further.
When you get your test kit, run a full set of tests and post them here. You will need to follow the SLAM Process
I suggest you read ABC's of Pool Water Chemistry

 

[an1vrsy]

Welcome to TFP! @Downfall

Your pool did not turn green, that green, overnight. As Marty strongly recommended add 5 ppm of free chlorine to your pool which means you need to add 1 and half gallons of 10% strength liquid chlorine each day until your kit arrives.

So, you'll need to find a source for liquid chlorine, local big box hardware store, Walmart, etc. To know how much to use at the bottom of each page here there is the Old Pool Math Webpage link. You can use that for now to know the quantities of the recommended pool chemicals to add to your volume of pool water. Good luck. You can do this.

 

[Downfall]

Thanks for the help. While I wait for my kit, do you think filling the pool up to the brim and then setting the filter to backwash or waste until it is down to mid-level skimmer is a good idea to lower CYA?

 

[mknauss]

How do you know what your CYA level is?

 

[Downfall]

How do you know what your CYA level is?

According to the test strips I have for now, it appears to be close to or at 100 unless it is just way inaccurate

 

[mknauss]

Your choice. Only a test strip can even sort of approximate is pH. Everything else, pure guess.

 

[IceShadow]

Wait until you get your kit to make changes to the pool. Until then just add 5ppm chlorine daily to help keep it at bay.

 

[YippeeSkippy]

When Marty says you need 5ppm of chlorine..... this is know how to find out how much to add

By using PoolMath I can see that-
62 ounces of 6% plain bleach = 1ppm FC
38 ounces of 10% Liquid Chlorine = 1ppm FC
32 ounces of 12% Liquid Chlorine = 1ppm FC

You can use this baseline to do the math you need but your best option is to learn how to use PoolMath. Either the App on your phone, or the old classic web version found on the bottom of TFP on computer.

Maddie

 

[Downfall]

Ok thanks all my test kit will arrive in 3 days but more rain is on the way (great!)

What can I do to prevent further build-up besides add 5ppm daily should I throw my solar cover over the pool to keep debris out or just leave it be? Thanks

 

[YippeeSkippy]

Brush! Brush! Brush! Some algae will build up on walls and it makes a icky film over itself (called Biofilm) as a protective barrier. To disrupt this biofilm brushing helps and that lets the chlorine in the pool get at the algae and duke it out.

Call it exercise

Maddie

 

[Downfall]

FC 8
pH 7.8
TA 200+ I think? (hard to test this one seemed to go from blue to blue yellowish but couldn't really tell when it switched)
CH 325 PPM
CYA 65

I currently use 3 chlorine tablets with the chlorine skimmer on half feed (was using 6 tablets full strength before that is what spiked my CYA I believe) should I change that at all? Here is how the pool looks now after I adding like 10gals of liquid chlorine first night and then kept PPM up at night with lots of brushing got a lil more vaccuming to do but what should I add from here? algacide or metal out?

 

[IceShadow]

Your CYA is already fairly high. Stop using tablets. (Note, you can’t tell what CYA levels are between two lines as the scale isn’t linear, so just round up and consider your CYA at 70.) Use only liquid chlorine to chlorinate.

You need to follow and finish the SLAM Process. This isn’t a one time shock process - you test your FC frequently and bring the FC using liquid chlorine up to the SLAM level for your CYA. You test at least 3 times a day and up to every hour or so. This elevated level of FC will kill any algae, along with frequent brushing and vacuuming.

Read the SLAM Process article - it tells you when you can stop. There are three criteria. Your pool looks fairly clear, so you probably won’t be in it for too long, but those green patches worry me.

Algaecide does nothing you need. It can help when you close the pool, but for standard use it doesn’t do anything that chlorine won’t do, and it can add harmful things to the water. “Metal out” typically just hides the metals in the water by making them more soluble in it. The only way to remove metals is to exchange water. Do you have a history of metals in the water?

 

[Downfall]

Your CYA is already fairly high. Stop using tablets. (Note, you can’t tell what CYA levels are between two lines as the scale isn’t linear, so just round up and consider your CYA at 70.) Use only liquid chlorine to chlorinate.

You need to follow and finish the SLAM Process. This isn’t a one time shock process - you test your FC frequently and bring the FC using liquid chlorine up to the SLAM level for your CYA. You test at least 3 times a day and up to every hour or so. This elevated level of FC will kill any algae, along with frequent brushing and vacuuming.

Read the SLAM Process article - it tells you when you can stop. There are three criteria. Your pool looks fairly clear, so you probably won’t be in it for too long, but those green patches worry me.

Algaecide does nothing you need. It can help when you close the pool, but for standard use it doesn’t do anything that chlorine won’t do, and it can add harmful things to the water. “Metal out” typically just hides the metals in the water by making them more soluble in it. The only way to remove metals is to exchange water. Do you have a history of metals in the water?

The metals likely coming from my well water which I use to fill the pool, I know I have high iron because I have to use RO system for my house. I have a huge bucket of chlorine tablets I would like to get some sort of use out of them instead of just wasting them, any ideas there? Once I run out I will switch to liquid chlorine.

 

[an1vrsy]

You mentioned in post #4, you wanted to lower CYA. You are already at 70, round up from 65. If you use those tablets in the bucket your CYA will rise again. You do not want to drain water to lower CYA just because you want to use the tablets that add CYA.

Tablets do not go bad. Keep the bucket dry and closed and you can use them periodically not everyday. Periodically could mean when you go on vacation for a few days so you aren't there to dose liquid chlorine manually.

 

[IceShadow]

If you want to sequester the metals, you can. Personally if I had high iron I’d raise the FC to SLAM levels, let the pool go green/brown from precipitating iron, then filter it out with polyfill in the skimmer to get rid of it for good.