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Hot Tub Care

A properly balanced hot tub does not smell however most spa owners complain about the smell of their water - this means that your hot tub is not balanced properly! Foamy water in your hot tub is another indication that you are not caring for and maintaining the tub properly. Caring for a hot tub is not especially difficult once you understand the nature of chemical interaction. If you are just starting out then be sure to read the 10 minute pool & spa chemistry crash course.

If you have been caring for a hot tub for a while already but still suffer from foamy water or water that is not clear or smells bad then be sure to follow the tips on this page:

The Most Important Hot Tub Chemical

Well, they are all important really. You need sanitizer to prevent a "Swamp Thing" mutant from growing and if you can cook shrimp in your spa because the water is so acidic this is also very bad. Chances are that you know these tips already. The most important thing that you probably aren't doing in terms of chemical maintenance is using oxidizer. Using oxidizer is incredibly important in a hot tub and further to this - you have to use it the right way!

Potassium Monopersulphate
Oxygen is a strong oxidizer and the basis for ozone systems. You can, and should, manually add oxygen to the water regularly and for multiple reasons. Oxygen will oxidize bacteria and organic debris in the water directly which is extremely important in reducing your exposure to sanitizer chemicals like chlorine or bromine. Additionally, adding an oxidizer to the water will reactivate spent bromine salts in your water. This is especially important since most hot tubs do use bromine. Instead of adding more and more bromine to your water you can reactivate the bromine salts already in the water and use them over and over again. When used properly oxidizers such as MPS (potassium monopersulphate, non-chlorine shock) can and will improve water clarity, improve water safety, reduce exposure to harmful sanitizer chemicals and reduce or completely eliminate "hot tub smell".

Use MPS every time you get out of the spa - The majority of bacteria enters the hot tub when you use it. Every time you finish in the hot tub you should add 1 tablespoon of MPS per person, per hour of use. Adding oxidizer directly when you finish in the spa is the most important time to use this chemical. It will oxidize bacteria and organic debris directly as well as reactivating the existing bromine in the water when you need it most. This one step will reduce or eliminate "hot tub smell" in almost every case.

Use MPS at least once per week - Whether you use the hot tub or not you need to be oxidizing regularly. You should add a 1/4 - 1/2 cup of MPS to your hot tub every week whether the tub was used or not. Oxidizer dosing is required for bromine to work long term. There are some pretty scary things that can grow in bromine water that is not regularly oxidized.

Cautions About Oxidizer In Hot Tubs

If you do not usually add oxidizer to your hot tub there are some cautions that you need to be aware of. Oxidizer reactivates spent bromine and oxidizer dosing will have a secondary effect of also increasing your sanitizer levels. If you already have a high sanitizer level or have recently added bromine sanitizer then limit your oxidizer dosing until the sanitizer level has reduced to avoid over sanitizing your water.

Another concern with adding oxidizer to hot tub water is that it will vent oxygen. When you add oxidizer to your hot tub you should leave at least half of the lid open for 15 minutes - 30 minutes after dosing. This will dramatically reduce the amount of oxygen that gets stuck under your hot tub lid which can cause hazing to everything above the waterline in the spa.

How To Clean A Hot Tub Filter

If you have foam in your hot tub water then you almost certainly need to clean your filter. Hot tub filters are made from paper and will get saturated with oil from sunscreen, makeup, hair products, sweat and many hot tub additives like scents. Rinsing a hot tub filter does almost nothing in terms of cleaning it. You need to use a degreaser to clean a hot tub filter properly.

Hot Tub Filter Cleaner
Hot tub filter cleaner is a product that is designed to cut through grease and oil. This is incredibly important since this is the only way to clean a hot tub filter properly. Using hot water in addition to the filter cleaner will help to cut grease and clean the filter quickly. Be sure to rinse your filter thoroughly before using in the spa again. A very handy tool to help with rinsing out the pleats in your filter is the filter cleaner comb. It is also possible to use granular automatic dishwasher detergent to clean hot tub filters as this soap is designed to cut grease and to be anti-foaming. The only concern with this is that this type of detergent will commonly contain phosphates which are something you definitely do not want in your hot tub. If you use automatic dishwasher detergent you had better be sure to rinse your filters extra carefully before returning to the spa.

How To Clean A Hot Tub

If you own a hot tub then you must be flushing the pipes in your spa on a regular basis. Every time that you drain and refill the hot tub, which should be every 3 months on average, you need to perform a pipe flush before draining the old water. Almost all of the bacteria in your hot tub exists in the form of bio-film which is a sticky substance inside of your plumbing lines. This bio-film is a food for bacteria as well as providing a layer of mechanical protection to prevent your sanitizer from resolving this problem. If you are not pipe flushing then you are transferring all of the bacteria from your old water directly into your new hot tub water.

Hot Tub Pipe Flush
When you use a pipe flush product you will want to remove the filters from the hot tub first. You also will want to close all air lines and open all jet lines on the tub. Pipe flush is added to the old hot tub water and then you run your jets on full blast for a minimum of one hour before draining. In some cases as with used hot tubs or very old hot tubs you might need to even refill and repeat this process or even let the tub soak overnight before draining in the morning. Once empty you can rinse the tub and clean with the interior surface with white vinegar. When you refill be sure to use a filter that has been freshly cleaned to avoid recontaminating the water. It is not uncommon to have a foot or more of brown / black foam grow on your hot tub during the pipe flush procedure - this is an indicator of just how dirty it was inside of the plumbing lines!

If you take these three steps in addition to balancing your sanitizer levels and pH levels as covered in the pool & spa chemistry crash course then you will very likely be able to maintain a hot tub with safe, clear water that is completely devoid of "hot tub smell". If you have chronic problems with oil saturating your hot tub filters then you would likely benefit from adding an oil absorbing sponge to the water.

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