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How To Decide Whether You Need An In-line or Off-line Chlorinator

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One of the main questions customers ask when they are deciding to buy a chlorinator is, “How do I decide if I need an inline or an offline chlorinator?” Well, chlorinators play an essential role in keeping your pool healthy for your family. However, not all chlorinators were created equal. You need to consider the best option for your pool and family.

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Steps

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Step 1

What type of pool do you have? Determining whether the chlorinator is for an above ground or in-ground pool will greatly narrow your search.

Click Here to View Our In-Line and Off-Line Tablet Chlorinators

Step 2

Determine the size of your pool. Calculating the number of gallons your pool holds will factor in when choosing how big or small your chlorinator needs to be in order to keep your pool healthy. Click here to determine the number of gallons in your pool

Step 3

Brand- Do you your research. Bigger names are slightly easier to maintain for the simple fact that it is easier to find replacement parts if necessary, as opposed to having to replace the entire chlorinator. Also, check to see if the chlorinator comes with any additional features such as the self- cleaning option.

Click Here to View Our In-Line and Off-Line Tablet Chlorinators

Step 4

Next, you will need to decide whether you need an in-line or off-line chlorinator. It simply comes down to the question of whether or not you have room to place the chlorinator in-line with the rest of your equipment. In-line chlorinators are connected directly after the filter (or heater, if you have one) and should be the last piece of equipment before the water is returned back to the pool.

Step 5

Off-line chlorinators are typically used when an in-line chlorinator cannot fit into the existing system. The off-line chlorinator is connected through a bypass line off-line from the rest of the equipment.

Click Here to View Our In-Line and Off-Line Tablet Chlorinators

Step 6

Don't forget to check the chlorinator capacity. Ensure the size of the chlorinator you chose is sufficient for your gallon size pool.

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(1 to 25 of 25)

 Posted: 5/20/2021 

Can you hook up an offline Hayward chlorinator after the filter? I would like to replace my inline but due to configuration must place both tubes in one pipe after the filter. Thanks in advance.
 Reply

InyoPools Product Specialist  Posted: 5/21/2021 

You can install the offline chlorinator lines after the heater, but you want to make sure that the outline after the chlorinator is placed after the heater (if you have one.) 
 Reply

 Posted: 4/10/2021 

Hello I’m thinking about purchasing a automatic chlorinator. I’m looking at my configuration to see if I have room for an in line. Would this be hooked up after the output of the heater? If so I should be ok as there is plenty of exposed pipe. Also can you recommend a good in line chlorinator for a 10k gallon pool. I have pentair fns plus so I would like to stick with them.
 Reply

InyoPools Product Specialist  Posted: 4/16/2021 

The chlorinator should be the last piece of equipment on your filtering pad. It should be mounted after your heater, with a check valve between the two to prevent the backwash of super chlorinated water into the heater if the pump loses pressure.For a pool that size you could go with something simple like the Pool Chlorinator Inline 9 Lbs. - PL0001.
 Reply

 Posted: 3/4/2021 

I have an offline chlorinator. Because the inlet is connected before the filter and there is a lot of pollen in my area, the chlorinateur inlet often gets clugged. The chlorine's level then drops drastically and before I notice that, my water turns greenish. I will change my chlorinator this year for an inline model. Hopefully, that will solve my problem.
 Reply

InyoPools Product Specialist  Posted: 3/4/2021 

Have you considered keeping your current chlorinator but just moving the inlet port to a piece of pipe after the filter?
 Reply

 Posted: 6/10/2022 

Thanks, did this and it fixed my issue.
 Reply

InyoPools Product Specialist  Posted: 6/15/2022 

Great! Love to hear it.
 Reply

 Posted: 3/18/2020 

Hi. I have a 24,000 gallon inground pool, currently with an inline chlorinator (Pool Frog). It's old and needs to be replaced. I could install another inline chlorinator (like a Hayward CL200), however I am better off with an off-line model so I can just have straight 2" PVC to my returns vs. the restricted inner diameter of the CL200? Thanks
 Reply

InyoPools Product Specialist  Posted: 3/19/2020 

If you want a less interrupted flow through the system, I would choose the offline. Just to make you aware, there is the Inline Hayward Chlorinator 2 Inch Slip, but the vessel's ports are the same as the standard CL200.
 Reply

 Posted: 3/19/2020 

So, even though the Haywards have 1.5 or 2" inlet/outlet pipes, both have the small (maybe 1") internal diameter opening that I see inside the CL200? I don't understand why anyone that understands this would want to install an inline chlorinator, when the offline allows continuous unrestricted flow through whatever other pipes (2" in my case) are in the system. Thanks for your help, I'll be looking at an off-line installation..
 Reply

 Posted: 2/23/2020 

I have an above ground 24ft x 54 in pool. I have an ozonator that works on my pool as well. No heater just pump, filter and ozonator. What would be the best option for my pool, off line or inline?
 Reply

InyoPools Product Specialist  Posted: 2/24/2020 

As we mention in the guide, the main factor on whether to use the inline or offline chlorinator is if there is enough space on the plumbing line to mount the inline. Other than that, it is personal preference. So, if you have enough space, you may use the inline chlorinator; if you do not, use the offline.
 Reply

 Posted: 10/23/2018 

Do you suggest the Rainbow 320 chlorinator or the Hayward CL200 Chlorinator?
 Reply

InyoPools Product Specialist  Posted: 10/23/2018 

Hello Patrick - I would recommend the Rainbow 320 over the Hayward CL200 chlorinator. The lid on the Hayward chlorinator becomes very hard to remove. The reason for this is that the o-ring expands and makes it very difficult to remove the lid. The Rainbow 320 does not have that problem.
 Reply

InyoPools Product Specialist  Posted: 10/23/2018 

I would suggest the Rainbow 320 chloorinator as where the pipe connects underneath the chlorinator is 2" in diameter where the Hayward CL200 reduces to about 3/4" which really restricts water flow and increases pressure in your system.
 Reply

Anonymous  Posted: 10/23/2018 

Please post the link to the Rainbow 320 chlorinator so I may purchase this chlorinator.
 Reply

InyoPools Product Specialist  Posted: 10/23/2018 

Here you may view the Rainbow 320 Chlorinator.
 Reply

InyoPools Product Specialist  Posted: 7/17/2017 

Anonymous (chlorinator) - The standard Rainbow 320 Inline Chlorinator will work well for your size pool.
 Reply

Anonymous  Posted: 7/13/2017 

Hi. I have enough pump house room to fit an inline chlorinator but I am not sure of the size I require. Our pool will be 10.7m x 4.2m with a sloping bottom. Shallow end is 1.0m & deep end is 2m. I am looking at the Rainbow feeders. Can you tell me which one I should select please. Thank you.
 Reply

InyoPools Product Specialist  Posted: 2/28/2017 

Chlorinator - Many people use the Rainbow 320 Inline Chlorinator for your size pool.
 Reply

Anonymous  Posted: 2/28/2017 

We can use a in-line chlorinator (3" tabs). Our pool is in ground about 9000 gal what size do I need?
 Reply

 Posted: 1/12/2017 

Nicely done but when running the spa and pool returns at the same time you'd be heating your pool water. Is this the set up most people use?
Jim
 Reply

InyoPools Product Specialist  Posted: 1/19/2016 

Rpswat - For your size pool I would recommend a high capacity chlorinator like the Rainbow HC-3315 High Capacity Auto Feeder. It will treat a pool with up to 97,600 gallons of water. This size gives you the capability to super chlorinate during heavy use in hot weather.
 Reply

 Posted: 1/15/2016 

What options are available to add a chlorinator to a 56,000 gal pool?
 Reply