3 Smart Alternatives to Pool Chlorine

Chlorine is the most widely used pool sanitizer in the world. However, many pool owners are worried about the chemical’s toxicity. Chlorine can be very dangerous, especially in its gas and granular forms. Those who want a pool without the harshness of chlorine don’t have to look any further.

Three smart alternatives to pool chlorine include bromine, ozonators, and biguanides. Bromine is softer on the skin and is more resistant. Ozonators release O3 to oxidize the pool and remove organic matter. Biguanides use PHMB to collect debris at the bottom of the pool for a vacuum to remove.

In this article, I’ll explain everything you need to know about bromine, ozonators, and PHMB (biguanides). I’ll also show you how you can reduce your pool’s chlorine usage and how you can shock a pool without chlorine.

Try Bromine

Bromine is a very popular chlorine alternative. It’s often used in spas and pool-spa combos. You can use bromine to safely sanitize a swimming pool, but it’s always important to wear safety gloves and glasses. Bromine typically isn’t as harsh as chlorine, though.

The Spa Depot Bromine Tablets are excellent for hot tubs and swimming pools. They work well at high temperatures, which is great if your pool is always in direct sunlight. Each five-pound bucket has enough bromine for several months. Place the bromine tablets in a floater and enjoy silky-soft sanitization.

To learn more about using bromine in your pool, review the pros and cons below.

Pros of Bromine

• Bromine feels soft on the skin. It reduces the surface tension and doesn’t add the grittiness of chlorine. Furthermore, bromine doesn’t have the harsh smell of chlorine, nor does it release as much powder and gas. Bromine is all around more comfortable on the skin for most swimmers.
• Bromine is more resilient to heat. It’s a popular choice for spas due to its heat resistance. However, bromine works very well in swimming pools with solar covers, heaters, and direct sunlight. Unlike chlorine, it won’t evaporate as quickly from the sun’s harsh UV rays.
• Bromine isn’t consumed by algae as quickly as chlorine. Algae and chlorine neutralize each other. While bromine is removed by algae, it can withstand a much bigger algae bloom than chlorine. This effect is enhanced in warmed water due to the aforementioned heat resistance.

Cons of Bromine

• This chemical costs more than chlorine. Bromine is extremely strong, so companies often charge more for it. You’ll have a slightly higher maintenance bill for your swimming pool. However, many pool owners are fine with the price hike because it’s much more effective during the summer.
• Bromine doesn’t last as long in the water as chlorine. Pool chlorine needs to be added weekly, but bromine often needs to be added once per four or five days. Always test your pool’s bromine levels before adding more of the chemical. You can use a solar blanket to prevent unwanted chemical loss.

Use an Ozonator

Ozonators aren’t too common but they provide an excellent alternative to chlorine. Ozonators hook into the pool’s equipment pad. They release O3 into the water, removing organic matter that causes algae and other unwanted contaminants.

Try the A2Z Ozone Generator to reduce your pool’s chemical usage by up to 95%. This generator replaces your standard sanitizer and keeps your pool feeling soft and healthy. Ozone generators are some of the safest forms of pool cleaning. Plug this compact machine into the pool’s plumbing for instant sanitizing.

Read the pros and cons of ozonation below if you’re thinking about getting one for your swimming pool.

Pros of Ozonation

• Ozonation has the least amount of side effects. It doesn’t add harsh chemicals or need nearly as much chlorine and bromine. People with chlorine sensitivity often choose ozone generators because they don’t interfere with the swimming environment. They also don’t add nasty chemical odors.
• You don’t have to add a sanitizer weekly with ozonation. While some people add a little bit of chlorine every couple of weeks to fend off algae blooms, you don’t need a primary chlorine sanitizer with an ozone generator. Your weekly maintenance schedule will be much easier and cheaper, too.
• You can plug an ozone generator into your pool’s equipment pad and forget about it. It doesn’t require constant maintenance or adjustments like saltwater pools, chlorine feeders, and so on. You also don’t have to worry about getting granular chlorine or liquid chlorine on your hands and clothes.

Cons of Ozonation

• Regions with a lot of debris can grow algae quicker than an Ozonator can handle. I highly recommend adding a weekly or bi-weekly algaecide to prevent unwanted blooms. Ozone generators are excellent for maintenance purposes, but they’re not the best at eliminating algae and other invasive contaminants.
• Some pool services won’t deal with pools that use ozone generators. They often rely on chlorine, which means they’ll either avoid or turn off the ozone generator. However, this isn’t much of an issue if you intend to maintain the pool without a service. Ozone generators reduce chemical usage, so the schedule is drastically reduced.

Consider Biguanides

Biguanides clump and remove debris from the pool, making it clean and clear. If you choose biguanides as your sanitizer, you have to remove the chlorine from the pool. There can’t even be a trace of chlorine in the water. Once the biguanides push the debris to the pool floor, your pool vacuum can remove it.

Baquacil Sanitizer is the most popular biguanide kit available. This sanitizer clumps the debris and adds an algaecide to prevent and remove algae around the clock. Each kit includes four gallons of Baquacil. Every gallon has enough for 80,000 gallons of water per week.

For more details about using biguanides in your pool, read on.

Pros of Biguanides

• Biguanides are the only complete way to never use chlorine or bromine. Ozone generators need a little bit of chlorine if they encounter massive algae blooms. Bromine is a great alternative, but it’s still considered a strong chemical. On the other hand, biguanides don’t need additional sanitizers.
• Most biguanides contain an algaecide, which saves a little bit of time and money. These algaecides prevent algae blooms, but they also help remove minor algae clusters. You can quickly remove them from the pool with a brush, vacuum, and proper pump circulation for a few hours.
• They make the pool feel much softer. Much like bromine, biguanides reduce the pool’s surface tension. There’s no chlorine, so the stereotypical gritty feeling isn’t present. Biguanides also make the water feel a bit thinner (for lack of a better term). This feeling is often described as silky smooth.

Cons of Biguanides

• You’ll have to empty your pool filter often if you use biguanides. This chemical clumps the debris, all of which ends up in your pool’s filter. Always clean or backwash the filter when the pressure gauge gets to 25 PSI. You can use a robotic vacuum to prevent some of the debris from getting into the debris.
• Low-end pool vacuums will clog quickly with biguanides. The thick clumps gel inside of the vacuum. Never use biguanides unless you have a mid-tier (or better) pool vacuum. Review our top pool vacuums for algae if you want to upgrade your setup before switching from chlorine to biguanides.

How to Reduce Your Pool’s Chlorine Use

To reduce your pool’s chlorine use, try these suggestions:

• Use a UV light. UV lights are installed in and around the pool to eliminate algae and other organic matter. The only downside is that they take a little while to work, and you won’t be able to use chlorine or bromine. UV lights immediately break apart the chlorine and bromine, so they’ll have no effect.
• Switch to a quad DE filter. Quad DE provides the finest filtration in the pool industry. When paired with water clarifiers, you can filter up to five times smaller than the best sand filters on the market. These filters are affordable, easier to clean than traditional DE filters, and don’t require backwashing.
• Get a high-quality robotic pool cleaner. Robotic pool cleaners remove debris from the bottom and sides of the pool. You won’t have to filter the pool as often or add too many sanitizing chemicals because there won’t be much debris. You can run a robotic vacuum throughout the pool for several hours daily without spending too much electricity.
• Consider copper ionization. This process takes advantage of copper’s natural ability to kill algae and other organic matter. You can pair copper ionization with chlorine for double the effectiveness. The only downside is that too much copper in the water causes discoloration. Make sure you test and maintain the copper levels regularly.

Can You Do a Pool Without Chlorine?

You can do a pool without chlorine, but you can’t realistically maintain a swimming pool without chemicals. People often switch away from chlorine, thinking it’ll make the water chemical-free. However, chlorine is one of many chemicals needed to safely maintain a swimming pool. UV lights, ozone generators, and copper are a few safer alternatives.

Your pool needs all sorts of chemicals to keep the water clear. There’s a reason lakes, rivers, and other natural bodies of water are rarely clear! In fact, the only clear water sources are extremely cold because the low temperatures prevent algae blooms. You can keep your pool icy cold, but it’ll be uncomfortable for swimming.

A chemical-free pool isn’t possible because your pool needs the following chemicals to stay clean and clear:

• Sanitizers (try the chlorine alternatives mentioned above)
• Alkalinity and pH adjusters
• Algaecides
• Calcium hardness
• Cyanuric acid (AKA a stabilizer, CYA, or pool conditioner)

If you don’t want to use chlorine, you should add oxidizers to the list and remove cyanuric acid. CYA is used to protect chlorine from natural evaporation. However, most pool chlorine has oxidizing properties. You won’t need the cyanuric acid without chlorine, but you’ll need an oxidizer to maintain the water’s clarity.

Most pool experts recommend weekly or bi-weekly shock treatments. I always suggest that people with chlorine pools or salt water pools shock their pools weekly during the summer and bi-weekly during the winter. However, you can shock your pool without chlorine if you’re using one of our suggested chlorine alternatives. Read on for more information.

How Do You Shock a Pool Without Chlorine?

To shock a pool without chlorine, follow these steps:

1. Add potassium peroxymonosulfate to your swimming pool. This chemical always comes in different dosages, so it’s important to follow the manufacturer’s instructions. Keep in mind that it doesn’t prevent algae, but it can oxidize the water and get rid of excessive cloudiness.
2. Turn on the pump for about 15 to 30 minutes to circulate the potassium peroxymonosulfate. I suggest brushing the pool’s floor and walls to mix the chemical as much as possible. It’s important to scrub the algae to help the chemical oxidize the water.
3. Don’t add chlorine or other sanitizers for a couple of hours. Harsh chemicals can damage or prevent this shock alternative from oxidizing the water. You’ll end up with a cloudy chemical soup.

It might seem like you have no chlorine after shocking the pool, but make sure you test the Total Chlorine, not the Free Chlorine. High chlorine concentrations will affect all of the chlorine alternatives listed throughout this article.

Are There Risks to Using Pool Chlorine?

There are risks to using pool chlorine, but every pool sanitizer has risks. Chlorine is dangerous to handle without safety gloves and glasses. However, it’s safe when diluted between 2ppm to 5ppm in the swimming pool. The only other risk is if you’re allergic to chlorine.

If you want the numerous benefits of pool chlorine without using concentrated chemicals, you can convert your pool to saltwater. Saltwater is softer, cheaper, and healthier for swimmers. You can combine saltwater pools with copper ionization, robotic pool cleaner, water clarifiers, and high-end pool filters for the best results.

There are various risks for every pool chemical. Proper handling is paramount. That being said, these chemicals have been tested repeatedly to ensure they won’t cause harm in diluted swimming pools.

Jonah Ryan

Jonah has worked for several years in the swimming pool industry installing and repairing equipment, treating pools with chemicals, and fixing damaged liners. He also has plumbing and electrical experience with air conditioning, ceiling fans, boilers, and more. When he’s not writing for Temperature Master, he’s usually writing for his own websites, LawnCareLessons.com and DIYByHand.com.