Low Chlorine levels

Dandy21

Member
May 7, 2021
11
Ottawa
Pool Size
64000
Surface
Vinyl
Chlorine
Liquid Chlorine
Hey there,

Opened my pool and the water is clear but the levels are wacky. I shocked, added chlorine tablets and followed the calcium steps that the pool store recommended. After being told never mix chlorine chemicals together beforehand because they can go boom now I'm paranoid about putting stuff in the pool so I wanted to check here!

My FC is 0 but I have three chlorine pucks in the Chlorinator but I guess those don't keep FC levels high? Do I add bleach to the pool while the pucks are in the chlorinator or is that dangerous to do when you already have chlorine tablets?
 
Just add the LC to the pool, in front of the return to have it mixed well. The pucks are better for maintaining at a level but LC can help you raise FC more quickly. Ensure you follow the levels based on FC/CYA Levels
 
Ok cool. So adding liquid chlorine to the pool itself is fine at the same time as the chlorine pucks are sitting in the chlorinator. The pucks just maintain it to a point.

How does shocking a pool vs adding liquid chlorine differentiate? LC is just common maintenance whereas shock is for a big one-time chlorine "shock" for lack of a better word?
 
Welcome! We don't SHOCK our pools. Head over to ABCs of Pool Water Chemistry. We use liquid chlorine as our primary chlorine source. If we need to clear up the pool we follow the SLAM Process process. Way different than the Pool Store. We follow the FC/CYA Levels to determine our Free Chlorine levels.

How do you test your water. You should test yourself, nobody cares as much about your pool than you do.

See the following link for test kits Test Kits Compared. I use the TFT-100 best bang for your buck. you can get maybe cheaper on Amazon but how old are the chemicals inside. TFT-100 has FRESH CHEMS.
 
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In my pool (~15,000gal), one bag of "shock" (TriChlor or CalHypo) or one gallon of liquid chlorine will raise the chlorine level by approximately 4ppm. So in theory, they should be similar. When the pool needs to be "shocked", however (ie "SLAMMED"), I use more than one bag and I don't use liquid chlorine.
 
You would also need to make a major decision if you're sticking here with TFP or if you plan on going to the pool store as we have a different and tested approach to pool care and they don't mix. You can't have it both ways.
 
All good advice thank you and I will go through all those suggested guidelines.

So the fact that I have Chlorine tablets - do I ditch those in favour of liquid chlorine solely or both can be used in tandem np?
 
For starters you'll need to get yourself one of the recommended test kits. THIS ONE is what I use. You can get the speed stirr from them too which makes testing more uniform results.Use poolmath and add 5ppm of liquid chlorine daily till the kit arrives. Once the kit arrives do the complete test as per the instruction card and post it so we can give you proper guidance.
 
How does shocking a pool vs adding liquid chlorine differentiate? LC is just common maintenance whereas shock is for a big one-time chlorine "shock" for lack of a better word?
Here is a good video. Actually TFP has many good videos on YouTube.
 
So the fact that I have Chlorine tablets - do I ditch those in favour of liquid chlorine solely or both can be used in tandem np?

The tabs can come in handy for example when going on holidays, as long as you plan for it and make sure that the CYA will not get too high over this period.
Do I add bleach to the pool while the pucks are in the chlorinator or is that dangerous to do when you already have chlorine tablets?

As Herman already explained, it is safe as long as the different chemicals only get together in the main pool vessel. In a diluted way - don't pour a load of Trichlor into your pool and then pour some liquid chlorine straight over it. Give chemicals time to mix in before you add the next chemical.

It would be a very bad idea to add liquid chlorine (or other forms of dry chlorine like cal-hypo) via your chlorinator. Even after the pucks have long dissolved, the residues can be enough to trigger an explosion.

A device designed for a specific type of chlorine should only ever be used for this type of chlorine.

And never ever put that remainder from your last chlorine tub into your new chlorine tub - you might realise too late that you accidentally grabbed the wrong tub from the store.
 
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How does shocking a pool vs adding liquid chlorine differentiate? LC is just common maintenance whereas shock is for a big one-time chlorine "shock" for lack of a better word?

The problem is the innocent word "one-time". That might be (if you're lucky) just enough to remove the green tinge from the pool. But you can be sure that there will be algae left in the pool, and the problem will return.

Great for a pool store, who can keep selling you "shock" on a regular basis. Ideally in the form of Dichlor, so that soon they will be able to tell you that you have "Chlorine Lock" and you have to drain and refill your pool, so that they can sell you the whole shebang of pool chemicals again. And again. Until you find TFP.

That's why TFP uses the acronym SLAM, which stands for "Shock Level And Maintain".

Actually, it might over time have turned into a recursive acronym: "SLAM Level And Maintain".

The important bit is the "M": SLAM Level has to be Maintained until you pass all three success criteria of the SLAM Process.
 
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