Blue cloudy water with no chlorine reading after double shock

Hello Experts,

My pool turned green and then pool store recommended to double shock the pool and run clarifier. I did and pool turned blue but very cloudy and I dont get chlorine reading. I did brushing and also put algaecide but still pool is cloudy. Here is my current reading. Please advice.

When did you double shock the pool?

Do you have a test kit?

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I did last weekend and yes I have test kit. I didnt see any chlorine so went to pool store to confirm. Attached screenshot is after the double shock and 24 hours after running clarifier.

What kind of test kit do you have?

Have you put any chlorine in since last weekend?


I have one with paper strips and also liquid one. I tested in both. I was hoping after double shock my chlorine level will go up but it didnt. So pool store asked me to use chlorine stablizer i.e. chloring tablets to increase the chlorine levels. RIght now i have chlorine tablet in floater since yesterday, i left it overnight and tested this morning but still no chlorine and its getting cloudier.

Your stabilizer level (according to the pool store number) is fine and you don’t need any more unless you are using a SWG to produce chlorine.

If your pool was green you have algae growing and one shock isn’t gonna do it…but you don’t need to double shock the pool.

I’m assuming the chlorine tablets are Trichlor. Is that correct?

Tell me what kind of shock you used to shock the pool…Cal-hypo, Dichlorvos, Trichlor, Lithium-hypo?

Tell me how you normally chlorinate the water…Automatic chlorinator, Tabs in floater/skimmer, Granular chlorine (if so what kind), liquid chlorine

Have you run the filter continuously since you shocked the pool?

what type of filter do you have?

Here is the shock I used;

Yes i am runing filter continously.

Its sand filter

chlorination is done via Tabs in skimmer.

I will confirm the chlorine tablets in some time. I forgot the brand name.

Sorry but I don’t read Spanish. Please look at the Active Ingredient on the bucket and tell me what kind of shock it is

Actually, I figured it out. The hth extra is 75% calcium hyperchlorite… Now I just need to know what type of pool you have, (Vinly, plaster/gunnite, concrete, fiberglass) and how many gallons of water it holds.

The pool volume is probably on the printout that you got from the pool store when they tested the water.

It above the ground pool, you can refer to this link its traditional one. Sorry, I dont know the technical names so refering you to link below.

And mine is 10000 Gallons pool.

I really appreciate your help.

Just to give more context, the pool is in this state after we opened pool for summer. It was closed all the winter.

If you need any additional info please let me know.

Thank you. You have a vinly liner pool. And the 42502 liters is a little over 11000 gallons of water.

You can start this in the morning. Let the pump run all night and if it needs to be backwashed in the morning, do that first.

**NOTE:**The amount of 75% Cal-hypo needed to shock your pool is 16 ppm.

2oz of 75% shock will raise the chlorine level in your pool by 1 ppm.

Then:

  • Take the tablets out of the skimmer
  • If the pump isn’t running, turn it on and let it run continuously until the pool is clear, backwashing the filter when the pressure indicates that it should be backwashed.
  • Using the test kit that has liquid reagents, get a fresh chlorine number.
  • Subtract the number you got from 16
  • Multiply that number by 2. This will give you the total amount of shock in ounces you need to add to the pool to get the chlorine to 16 ppm.
  • Dissolve the chlorine in a big bucket of water and pour it in the pool in front of the return

After 2-3 hours, vacuum the pool, backwashing the filter when the pressure says you should.

In the evening, brush the pool walls. Then take a new chlorine reading, subtract that number from 16, multiply that number by 2 and add that much chlorine to the pool.

The next morning, take a fresh chlorine reading, bring the chlorine level in the pool back to 16 and start the cycle all over. This will make sure all of the algae and any other organics are killed.

Vacuum the pool daily, in the morning, and brush the pool walls daily, in the evening. This will clear the pool up.

When the chlorine reading you take in the morning is 1 ppm or less than the chlorine reading you took the night before, and the water is clear, you are done shocking the pool.

At this point you should be able to run the pump on it’s normal cycle, let the chlorine level fall back to the 3-5 ppm range and put the tablets back in the skimmer.

If you have any questions let me know

J

I really thank you for your advice.

I have one question. How to get the reading for chlorine. Is there testing kit to give the number ?

‘When the chlorine reading you take in the morning is 1 ppm or less than the chlorine reading you took the night before, and the water is clear, you are done shocking the pool.’

so for my understanding when my morning reading is almost same as night with difference of 1 ppm reading this shocking is done correct ?

" let the chlorine level fall back to the 3-5 ppm range and put the tablets back in the skimmer."

how will chlorine falls back to 3-5 because last morning of this activity it will be 15ppm… do I need to drain the water ?

And vacuum can I use robot vacuum ?

This is liquid one I have… could please recommend which one to use to get reading of 16ppm

Ideally, you need a test kit like the Taylor K-2006 or the TF100 FAS/DPD test kit. They will measure chlorine up to 50ppm.

How high does your test strips go?

Strips can read upto 10PPM.

Sorry, I didn’t see your other questions.

“I have one question. How to get the reading for chlorine. Is there testing kit to give the number ?”

As I already stated, the Taylor K-2006 or the TF100 test kits will detect chlorine up to 50 ppm.

“so for my understanding when my morning reading is almost same as night with difference of 1 ppm reading this shocking is done correct ?”

And the water is clear. That’s where vacuuming the pool every day comes in. That will clear the dead organics.

“how will chlorine falls back to 3-5 because last morning of this activity it will be 15ppm… do I need to drain the water ?”

You simply stop adding chlorine to the pool until the chlorine falls back to the normal 3-5 ppm level. Then you resume your normal chlorination method. No need to drain water.

“And vacuum can I use robot vacuum ?”

Yes you can, but be mindful of what kind of filters you have in the robot. Most robots come with 2 kinds of filters. The zig-zag or “fan” looking filter will catch bigger particles like leaves, bigger pieces of dirt an debris. The fine mesh looking filters will catch smaller particles like dead algae. So if you’re using the fine mesh filters, check them periodically to make sure they aren’t clogged.

As you vacuum, what the filter doesn’t catch wil be suspended in the water. The filter will catch part of this but sand filters only filter particles down to about 20 microns in size.

To help the filter you can put what is called a “sock” over the skimmer. The least expensive way to do this is to cut the foot part off of a woman’ stocking and stretch it over the top of the skimmer basket. But you must check the sock regularly because the dead algae will clog it and reduce water flow to the filter. When you see that it’s pretty covered, simply take it off, wash the gunk off of it and put it back on.

Pool supply companies sell a product called a skimmer sock. But if you decide to purchase a skimmer sock just be sure it will fit the smaller skimmer basket that most above ground pools have.

As for buying a test kit that will test for high chlorine levels, the only other suggestion I have would be to take a water sample into the pool company twice a day, once in the morning and again before they close in the evening. But be prepared for them to try to sell you additional chemicals (that you probably don’t need)

J