Confused - levels seem right though pool is green

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When you pour bleach into the pool in front of a return you will notice it clouds the water so you can see it dispersing. Pour low to the water and slow enough that you don't splash. With plaster it's not so critical how fast, if it was vinyl you want to be more careful so as not to damage the liner.

When buying bleach this is a handy app that will tell you how much you're paying for the bleach when comparing different sizes and different strengths. Make sure you don't get anything scented or splashless/easy pour. They can contain additives that create problems like foaming. Chlorine Price Per Ounce Calculator


When figuring out how much bleach to add remember that you need to input the strength of the bleach you are using. In "Pool Math" up at the top of the page you need to make sure you have the strength set for what you're going to be adding.
 
Andy, I just noticed that you updated your signature and that you are on well water.

Before you proceed with a full-on slam, can you look up the ppm of iron, if any, in your well water. If the house is new to you, you will find those numbers in your well/septic evaluation from the sale, I believe.

Also, please post a picture of the water, and let us know if it turned green gradually after being cloudy, or "suddenly" on adding chlorine.

Lastly, if you are able, if you do slam, you may find it easier if you do a partial drain to get your cya down by half, but we'd rather see your own cya tests from a good kit, as the pool store often gets this wrong.

AND if your well water supply does have iron and if this were causing any of your green, there are discussions about pre-filtering, etc. we should have prior to a water change. I don't want to inundate you with more info when you're new to this, so will check back first to see if you have metals in your well.

To get started, there's a link in my signature that will take you to an article about METALS.

Anyone who owns a pool fed by well water needs to get familiar with a different set of criteria before slamming, as slamming will also oxidize an sequestrants keeping the metals in suspension.

Sometime, these can wear off over time and cause a green tint to the water as well -- which is why doing the Overnight Chlorine Loss Test is important in determining whether you need to slam, or whether you need to retreat for metals.
 
Thank you all! I haven't found the water test from our purchase yet though have a note that says 'the nitrate and lead levels are fine...' - not that that tells us much. I would say the water turned green fairly gradually - and we didn't really add any chlorine. The last step we took was to try to lower the pH by adding Muriatic acid (because we thought it was preventing the Chlorine from working)... I've ordered the right test kit (it's on its way!) and did put in the bleach before we saw these latest posts. I did input all the right information into the Pool Math tool. I brushed the sides of the pool and it clouded up...and we are running our pump/filter continuously right now.
 
I started off with the same test kit, the 1004. Literally 2 minutes before typing this, I received the notice from UPS that my TF-100 has shipped!

This forum gives great advice, and has a wealth of information. Take the time to peruse it and print some of it for a quick reference guide.
 
Andy, if you're cloudy, and it was gradual, then I suspect its most likely organic and will require slam once you have your kit. But if anything strange happens re water tinting etc., feel free to pm me in case I miss it and I will come back to the thread to discuss post slam metal mgmt if needed ;)
 
Okay pool people - here's the update. We essentially performed a SLAM with liquid bleach (per my last post) - after about 3 days it cleared up. We now have our legit test kit and I came up with these numbers:
FC = 15 ppm
CYA = 60-ish
TA = 180
CH = 425
pH = 7.6 or so...

Looks like Alkalinity is a bit high - though it sounds as though that's not a huge problem unless pH is too high (it's on the high end though not really high...?). Looks like our target FC is about 7 - so we can let the current levels wane a bit and then need to keep it around 7 ppm... what else should we do now to keep it clear and swimmable?! anything we need to do about alkalinity or pH?

Thank you!!!!

- - - Updated - - -

Oh, also, what levels of Chlorine are ok for swimming? do we need to wait a bit or is 15 'ok'?
 
You've got it. You pH will probably rise, just bump it down with acid when it gets to 7.8, the TA will lower also. You can use the acid/aerate/acid method if you would like for it to go down faster.

It's ok to swim up to SLAM level.
 
You are good to swim up to your shock level for your CYA. Even at shock level the amount of "active" chlorine in the water is very very low - far less than municipal tap water.


PH and TA - if you routinely lower your PH to 7.2 you'll find your TA lowers. Where that balance settles will depend on a variety of things - fill water, rain, aeration, etc. It's not all that important as long as your CSI numbers are staying in the correct range.
 

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Okay - I'm back...had a couple of busy days. I measured the two keys again and plan to do the FC again in the morning for the overnight loss test... They are currently:
FC = 6.5-7
CYA - between 45-50...

We've had a bit of rain and also had the hose running into the pool to replenish so it seems to have cut the CYA quite a bit in the last week or so. I'll post the morning FC numbers and go from there...though it seems our FC levels have come down nicely from the SLAM levels and now we just need to keep it here (around 6-7) and we'll be good, right?

Cheers!
 
Do you have a photo of the water? Is there any haziness or cloudiness to the water? Can you clearly see screws on the deep end drain cover?

You will need a more precise measure of FC as a range will not help.

We also need an accurate CC result.

CYA is rounded up to the nearest number on the tub, so a result of 45 is rounded to 50.
 
So, I put in 13 drops and the water turned clear - as I started doing the CYA test I looked up and saw that the chlorine test water went back to a slight pink...one more drop (14 total) cleared it up for good - so I put 6.5-7.

I find the CYA test to be a bit odd to call a test accurate that is really pretty subjective as to whether you can see the dot through the top of the tube ...it was right around the 50 line so I should have just said 50.

I can send a picture tomorrow - though the water is very clear. This morning it was a little cloudier (every so slightly hazy) though it rained last night - this afternoon it was just clear as I remember. I didn't check to see if I can see the screws on the drain in the deep end though can look tomorrow.
 
The Fc test will turn pink if you let is sit so your Fc is 6.5.

Any cloudiness haziness etc. means you need to continue the SLAM.

You also need to have cc of 0.5 or less.

Cya is light sensitive so it must've done in full sunshine with your back to the sun, vial at waist level and hold with two fingers.


Sent from my iPhone using Tapatalk
 
How does the water look, any cloudiness, haziness? Can you see the main drain screws?

Well, the FC test shouldn't go up overnight, so a FC of 7 isn't expected. Consistency is key in testing. Below are the extended test kit directions on the FAS-DPD test. Here are the extended details on the rest: Extended Test Kit Directions

FAS-DPD Chlorine Test
FC and CC - Free Chlorine and Combined Chlorine

Rinse the sample tube with pool water.
Fill the sample tube with pool water to the 10 ml mark. The top of the sample will be curved. This curve is called a meniscus. The bottom of the meniscus should be level with the 10 ml mark.
Using the small spoon shaped end of the dipper, add one heaping dipper, or two level dippers, of R-0870 and swirl to mix. If the sample turns pink for a moment and then turns clear again, or if it turns brown, add another dipper of R-0870. If the sample remains clear the entire time, your FC level is probably zero, however it is best to verify that with an OTO chlorine test, since the FAS-DPD test is prone to the occasional false zero.
Swirling constantly and counting the number of drops as you go, add R-0871 one drop at a time. Continue adding drops until the color changes to clear. The pink color may become extremely faint before it goes away. Make sure that the sample goes completely clear.
Multiply the number of drops by 0.5 to get your FC level.
Add 5 drops of R-0003 and swirl to mix. If the sample remains clear, your CC level is zero.
If the sample turns pink again, add R-0871 one drop at a time, swirling constantly and counting the number of drops as you go. Continue adding drops until the color changes to clear. The pink color may become extremely faint before it goes away. Make sure that the sample goes completely clear.
Multiply the number of drops by 0.5 to get your CC level.
Dispose of the sample safely. It is best to pour it down the drain with the water running. Do not add it back to the pool.
Rinse the sample tube with tap water and store for next time.


Notes
Hold the dropper bottles vertically and squeeze gently, so that drops come out slowly and seem to hang on the tip of the dropper bottle for a moment before falling.
The exact amount of R-0870 powder used is not critical. The goal is to add more than you really need rather than using too little. Using too little R-0870 powder can throw off the results of the test. You need to use enough to bind to all of the chlorine that is present. Adding extra, within reason, has no effect. At very high FC levels it is likely that you will need to use more than the normal amount.
If left sitting on the counter, the sample will turn pink again one or two minutes after the test is completed. This is normal.
When measuring high FC levels, or measuring FC when the CC level is relatively high, it is important to move through the test quickly. Drops should be added about once per second, or slightly faster, swirling the entire time. You can slow down a little at the end of the test, to give you time to watch for the end point.
In rare cases the sample may turn cloudy. If this happens the test is still valid. You add drops until the sample turns cloudy white, i.e. the red/pink is completely gone, rather than waiting for it to turn clear.
Any MPS in the water will count towards the FC reading. Taylor R-0867 Deox Reagent can be used to eliminate this interference.
Over time, it is common for a cloudy residue to build up on sample tubes used for FAS-DPD chlorine testing. The residue can be removed by filling the sample tube with bleach, letting it sit for several minutes, rinsing, and then wiping throughly with a paper towel.
There isn't normally any reason to do this, but if you need more precision you can do this test with a 25 ml sample of pool water and multiply the number of drops by 0.2. In most situations the added precision is useless and simply wastes reagent.
R-0870 is DPD powder. The indicator in the powder turns pink when bound to chlorine. R-0870 powder gets darker over time and eventually starts to clump up. If it is clumped up, you should crush it back into a slightly lumpy powder before using it.
R-0871 is FAS-DPD titrating reagent. It should be a clear colorless liquid. If it turns a dark yellow color, it has gone bad.
R-0003 is DPD Reagent #3. It should be a clear colorless liquid. If it turns yellow, it has gone bad.
 
You can add acid to lower your PH to 7.2, but it isn't an urgent issue at the moment. Make sure you let 30 minutes pass between the addition of acid and chlorine... combing them will make chlorine gas which can be fatal.

The urgent issue, because you have cloudy water is that you need to continue your SLAM and keep your FC at 20 which is appropriate level for your CYA. Pool School - Chlorine / CYA Chart

You need to test and adjust FC back up to 20 several times a day.... the "M" is SLAM is maintain. Letting your FC to get to 8.5 will only let the algae multiply faster than you can kill it.
 

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