Choosing Your Sanitizer

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The two most predominately sanitizers for hot tubs are Chlorine and Bromine. Both do a great job, and each has its pros and cons. Whether using chlorine or bromine, you should keep either one at a sanitizer level of 3 to 5 parts per million.


Chlorine is sold either as Tri Chlor, CalHypo, or DiChlor. TriChlor.
CalHypo should only be used in swimming pools, not in Hot tubs.

DiChlor is the best chlorine available for hot tubs (why). This HT Chlorine only has DiChlor. When added to the water, it’s a fast-acting sanitizer that gives an instant reading (of what). It also has a nearly perfect pH reading level of 6.7, so there is little chance HT Chlorine will fluctuate the pH reading in your water.

The downsides to chlorine are:
It doesn’t last long, so you need to add it every other day to keep an adequate sanitizer level of 3 to 5 parts per million. If you let it go to zero, it will give off a chlorine scent.

Used properly, chlorine is a very effective sanitizer used in over a million hot tubs every year.

To add chlorine, turn on the jets and add one-half ounce for every 100 gallons. Then, for an average 300-gallon spa, add one and a half teaspoons every other day or when needed.


Bromine is considered by many the easiest sanitizer to use because it lasts a long time.
HT Bromine comes in a tablet form dispersed into the water through a bromine dispenser.

Add one tablet for every 100 gallons of water. For an average 300-gallon spa, put three tablets into the dispenser and set the valve about half open. For larger spas, add more tablets and open the valve a little more.

People choose bromine over chlorine because you don’t have to add it every other day. You only need to add a few tablets once a week, and you’re good to go.

One downside to bromine is that it is slow-activating. As a result, bromine tablets take up to 2 to 3 days before getting an accurate test strip reading.

If you forget to add tablets, your sanitizing level will drop to zero as your spa gets used. If that happens, you need to jump-start your spa water to get a sanitizing reading on your test strip. There are two ways to jump-start your bromine reading.

One is to add 2 ounces of HT Activator, wait a few seconds, and then add 2 ounces of Brom Bank, which is pure bromine.

The second is to add 2 ounces of HT Activator, wait a few seconds, and add a pre-packaged Sodium Bromide packet.

Both will give you a quick bromine sanitizer lever that will now show up on your test strip.


The choice between chlorine or bromine is simple.

If you don’t mind adding a little chlorine every other day and you like getting an instant reading on your test strip when you do, then chlorine may be your best choice.

If you don’t want to deal with caring for your spa every other day and you don’t mind jump-starting it whenever you forget to add tablets each week, then bromine is properly better for you.

The good news is they both work great. And if you ever decide to change from one to the other, be sure to drain your water first.


When someone uses their spa, they naturally bring in bacteria. So, when you get out, whether you’re using chlorine or bromine, make sure you shock your water with 2 ounces of HT Activator. If more than two people were in the spa, add one ounce for each additional person. Shocking your spa each time you use it is essential to keep your water crystal clear and healthy and lower the amount of sanitizer you’ll use.

A great way to reduce the amount of chlorine or bromine in your spa is using an HT Mineral Purifier.


Chlorine or bromine must be kept at a sanitizer level of 3 to 5 parts per million. With an HT Mineral Purifier, you can lower that level to 2 to 3.

Where most mineral purifiers use zinc or silver, our HT Mineral Purifier uses zinc, silver, and copper to purify the water. It helps reduce your sanitizer usage by up to 50%, but it also helps reduce the chemical scent sanitizer creates. It also helps protect your spa equipment.

One HT Mineral Purifier stick will last for four months, so it’s economical, and it’s easy to use by simply dropping it into your filter area or in the weir skimmer if one exists in your spa.