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Hot Tub Water Smell

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Hot tub water smells bad One of the biggest complaints among spa users is that hot tub water smells bad. How can you enjoy a relaxing and therapeutic soak in hot water if you are choking on smelly water? One of the most common lines of questioning that I deal with from hot tub owners relates to finding alternatives to using bromine as the sanitizer. There are, of course, alternative options however there are some pretty good reasons why bromine is conventionally used in hot tubs. If you are looking for an alternative to bromine because "bromine smells bad" then you will ultimately not be happy with switching to something else. Why is this? The answer may surprise you:

Properly treated bromine hot tub water has absolutely no negative smell

Really? You are probably doubting this claim since you have been in a great many hot tubs and most, if not all, had that same "bad" bromine smell. Again, you will be surprised to learn that this means those hot tubs, all of them, were not properly balanced. When you balance and maintain your hot tub water properly there will be no bromine smell, and the water will be crystal clear. The problem is that most people do not maintain their hot tubs properly. This is also the reason why I can only use my hot tub, the one that I maintain myself, and I would never get into a "friends" hot tub or (shudder) a commercial hot tub at a hotel. Once you have managed a hot tub water testing lab you quickly learn that most people have no idea what they are doing with their chemical balancing...it is amazing to me that more people don't die from Legionnaires disease! If you would like to know more about what a water chemistry specialist thinks about before they get into a hot tub, then read this article to learn about what you need to know before getting in hot water.

How To Get Rid Of Bad Smelling Spa Water

Hot tub water should not have any smell. If your hot tub water smells bad there is at least one thing you are doing wrong, if not multiple things. Hot tub care is more than just adding some bromine pucks to the floater every now and again. Consider this list of the most common reasons why your hot tub water might smell bad:

Change your water every 3 months - If you are keeping your spa water for longer than three months at a time then this will contribute greatly to having bad smelling water. You should change your hot tub water once every three months at maximum, and this assumes that the water has been optimally balanced at all times. If you struggle to maintain the chemical balance in your water and periodically deal with water turbidity, or green water, or pH levels out of range, then you should be changing your water more often than once every three months. Sure it is work, but if you want to have clean, clear and smell free water in your spa then this is the program you need to adopt.

Pipe flush every time you drain - Possibly the biggest offense that hot tub owners make is to neglect pipe flushing the spa before you drain your water. Almost all of the bacteria within your hot tub is not suspended in the water. Bacteria in a hot tub primarily lives inside of the plumbing lines, covered in a layer of bio film which acts as both mechanical protection as well as a food source for the bacteria. Sanitizer can not get to the bacteria because the bio film blocks it and running your jets will not clean it out. Before you drain your hot tub you should be running a pipe flush product to help strip away the bio film so you can actually start fresh with clean water. The lack of pipe flushing is the reason why your hot tub smells bad even when you have just filled it with fresh water.

Clean your filters properly - Cleaning your hot tub filters properly (and often) is one of the most important things you can do to help your hot tub water to remain clear and smell free. When you look at swimming pool filter systems it really puts into perspective just how undersized and cheap hot tub filters are. Cleaning all of the physical debris out of 500 gallons of "people soup" is a lot to ask from a tiny, flimsy piece of paper that is little better than a glorified paper coffee filter. You should have at least two filters for your spa so that you can have one that is clean and ready to go at all times. When it comes to cleaning, you must use a hot tub filter cleaner product. This product removes grease and oil which has saturated the paper. Washing a spa filter with a garden hose alone does essentially nothing to actually clean the filter. Use a degreaser for your filter every 30 days at absolute minimum, or more often if your tub gets a lot of use.

Once you are on the program of the three steps outlined above you are well on your way to stink-free spa water. Regular maintenance with your filters, water changes, and pipe flushing will eliminate or at least vastly reduce the amount of bacteria, oil and used chemicals that are in your water. This alone will go a very long way to eliminating "hot tub smell". The next step is to get a better understanding of the chemical maintenance process.

Balanced Hot Tubs Should Not Smell

You need to maintain the chemical levels in your hot tub to protect both yourself, as well as the hot tub, from damage. Most hot tub owners know the absolute minimum possible in order to have a hot tub that is functional. If you spend some time learning about how to balance the sanitizer levels, pH, total alkalinity and calcium hardness this will resolve 9/10 problems that you could potentially encounter. If you think you would benefit from a refresher in hot tub water chemistry then you can read this 10 minute water chemistry crash course.

There is some regular chemical maintenance that bromine hot tubs need that you are probably not doing which could help you reduce hot tub smell. In order for bromine to work effectively as a sanitizer it needs to have regular dosing of oxidizer. Also, once bromine is used up, and sitting dormant in the hot tub, it can be turned back into "active" bromine again by adding oxidizer. This relationship between bromine and oxidizer is very important if you want to maintain your hot tub water smell free.

There are two main ways which you should use an oxidizer in your spa. First we should identify what an oxidizer is, which is a form of shock that does not contain any sanitizer (bromine or chlorine), but only oxidizer like potassium monopersulfate. You need to make sure that you have a large supply of MPS (potassium monopersulfate) or non chlorine shock as this is the most common chemical that you should be adding to your water. Specifically you should use oxidizer in the following two ways:

Once per week - Once per week you should add 1/2 cup of MPS oxidizer to your hot tub for every 500 gallons of water. This treatment should be added whether the hot tub has been used or not in the previous week. This regular dosing of oxidizer will ensure that your bromine will be able to act as a sanitizer in the water and kill bacteria as it is intended. Adding oxidizer will increase the bromine level in the water so be sure that your bromine level is not too high already before adding oxidizer. It is possible that you will need less than 1/2 cup per 500 gallons of water if your bromine levels are already high as too much oxidizer could potentially raise the active bromine level too high.

Every time you use the spa - Every single time that you use your hot tub you are adding dirt, debris, skin, oil and bacteria to the water. This is when you should be adding oxidizer to the water. Each time you get out after using the spa you should add 1 tablespoon of MPS per person, per hour of use. This will directly oxidize the contaminants in the water, and will also serve to reactivate some of the spent bromine that is already in the water. Always leave the lid of your hot tub open after adding oxidizer to let it breathe. One hour would be the ideal amount of time, with 15 minutes being the minimum amount of time, that you should leave the lid open after adding oxidizer.

One of the biggest mistakes that hot tub owners regularly make is to just keep adding more and more bromine when they notice the bromine level in the spa is low, or zero. While sometimes this is the right course of action, 9 out of 10 times the same result can be achieved by using an oxidizer instead of more bromine. Once your bromine floater runs out you probably have enough bromine dormant in the water to run for another week or two just from oxidizer dosing. So you can either keep adding more and more bromine, or you can re-use the bromine that you already have in the water. Which sounds like the healthier option? As you can imagine, if you spend three months adding more and more bromine to the water, it is little wonder that the water smells a lot like chemicals. You still need to use bromine, but you can use much less by being more proactive with oxidizer dosing.

If you are wondering how much you can use the oxidizer shock in place of adding more bromine, you are free to do this so long as you have a measurable bromine level in your hot tub between 2 and 5 parts per million at all times. If you add the oxidizer but but still do not have a high enough bromine level then that is the point at which you can add some bromine pucks to the floater, or a small dose of granular bromine to the water.

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