Liquid chlorine vs Shock Question

robl45

Well-known member
Oct 27, 2007
931
Parkland, FL
I typically use Liquid Chlorine from the pool store. 2.5 gallon jugs around here, I believe 10% concentration, but I hardly need it as I have a salt generator. However sometimes with very heavy rain, or when away on a trip and something goes wrong I need some chlorine. Its a pain to transport so I thought I would try some normal shock. I bought the stuff below and was curious how it compares to a 2.5 gallon jug of the liquid chlorine. I tried to use the pool calculator and from what I can tell, one 2.5 gallon jug of chlorine is equivalent to 4 1lb bags of dichlor shock like below? Is that about right? Further, when putting in the shock, is it normal for it to take time to boost the chlorine vs the liquid?


I ended up dumping the whole 6lbs of shock into the pool as it wasn't having the immediate affect like the liquid normally does and then went and threw the liquid in as well. Stupid on my part and the pool is thoroughly chlorinated at this point, but I would like to figure out for next time as I would rather use the shock if possible the next time I have a possible algae situation as its much easier to store etc.
 
one 2.5 gallon jug of chlorine is equivalent to 4 1lb bags of dichlor shock like below
Sure, they both add about 32 ppm FC to your pool. Of course the dichlor would also add 30 ppm CYA to the water and drop the pH a LOT while the liquid chlorine just adds a bit of salt, but they will add about the same amount of chlorine.

6 pounds of dichlor will increase your FC by 50, your CYA by 45, and greatly lower your pH. Was that your intention?
 
  • Like
Reactions: Mdragger88
Sure, they both add about 32 ppm FC to your pool. Of course the dichlor would also add 30 ppm CYA to the water and drop the pH a LOT while the liquid chlorine just adds a bit of salt, but they will add about the same amount of chlorine.

6 pounds of dichlor will increase your FC by 50, your CYA by 45, and greatly lower your pH. Was that your intention?

Does the Dichlor take longer to do the job?

For my pool I"m always low on CYA with the salt generator and I am terribly bad with PH and the acid so it actually works out quite well. What does trichlor do that is different?
 
I don't understand the question, chlorine is chlorine once it is in the water.

If your chlorine is low then why would you want to increase your FC to 50 ppm? Unless your CYA is over 100 then that's way too high.
I didn't. I didn't realize. When I put in the liquid and I test a bit later, the chlorine is high, when I put in the Dichlor and tested and tested for a bit, it was only at 5, that is why I was wondering if it takes longer to dissolve or whatever.
 
Adding 50ppm fc, 45ppm of cya & a huge ph drop is alot of stuff going on with your pool at once. It’s not really recommended & can damage your surfaces & equipment.
What problem are you looking to solve & how are you testing your water?
What are your most recent test results?
Fc
Cc
Ph
Ta
Cya
Ch
Salt
 
  • Like
Reactions: Donldson
The test kid that was part of the trouble free pool kit. Chlorine and PH
It you mean the oto “yellow” test on the comparator block- it maxes out at 5ppm.
Use the fas/dpd test - the one with the powder that turns pink to accurately test fc & cc
 

Enjoying this content?

Support TFP with a donation.

Give Support
I typically use Liquid Chlorine from the pool store. 2.5 gallon jugs around here, I believe 10% concentration, but I hardly need it as I have a salt generator. However sometimes with very heavy rain, or when away on a trip and something goes wrong I need some chlorine. Its a pain to transport so I thought I would try some normal shock. I bought the stuff below and was curious how it compares to a 2.5 gallon jug of the liquid chlorine. I tried to use the pool calculator and from what I can tell, one 2.5 gallon jug of chlorine is equivalent to 4 1lb bags of dichlor shock like below? Is that about right? Further, when putting in the shock, is it normal for it to take time to boost the chlorine vs the liquid?


I ended up dumping the whole 6lbs of shock into the pool as it wasn't having the immediate affect like the liquid normally does and then went and threw the liquid in as well. Stupid on my part and the pool is thoroughly chlorinated at this point, but I would like to figure out for next time as I would rather use the shock if possible the next time I have a possible algae situation as its much easier to store etc.
Be careful of that stuff, especially the Clorox brand because it often contains copper. Can’t tell on the ingredients list of that one because it says other ingredients are in the product but don’t say what they are. Usually the copper containing stuff has “blue” in the name.
 
Last edited:
  • Like
Reactions: Mdragger88
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.