For a spa, we do recommend you drain it to get rid of all chemicals. However, H2O2 will not adversely interact with current pool chemicals and some will transition to H2O2 usage. If your pool is highly organically fouled, you may want to use a much higher initial level of H2O2 to kill the organics, drain this, and then go to the same maintenance levels as for a pool.

For a pool, it is not necessary to drain the pool if you do not want to until when you would regularly drain the pool while using pool chemicals. Or you may want to transition to H2O2 at that time. Hydrogen peroxide will not have any adverse reaction or interaction with pool chemicals. The level of H2O2 suggested below will vary by the amount of organic material that comes into the water (leaves, dust) and by pool usage that then also brings contaminating organics into the water. Within the context of the water volume in a swimming pool, increasing concentration to address high pool usage or high organic content can not reach a harmful level no matter how high a concentration you decide to use.

Below are the recommended levels. You may then adjust this later as you feel necessary.

NOTE – There are no hard and fast rules for pool and spa maintenance. Each pool or spa is unique and depends on the following factors:

  • Area of the country… heat levels, organic material entering pool or spa.
  • Type of water… hard, soft, etc.
  • Ultraviolet radiation levels… is pool or spa covered when not in use?
  • Level of use… how many times a day or week is it used.

All the above will affect maintenance programs. You will need to customize your own program to each pool or spa. Keep in mind that there is no danger of health problems even if you use H2O2 at too high a level for what is actually needed. Store bought H2O2 is at 3%. To get pool or spa levels to a 3% solution would be extremely expensive. You are looking at 100-200 parts per million for proper dosing, and even if you got to 1000 parts per million, you’d be nowhere close to 3%.

Getting started:

Many recommend shocking your pool or tub to start using hydrogen peroxide. Either Food Grade or Technical Grade can be used.

To “SHOCK” your pool or hot tub, a relatively high level is used at a ratio of 1 cup of 35% concentration for every 250 gallons. DO NOT RUN your pump continuously. Rather, run it only long enough to circulate the water and then turn off the pump. Ideally, you should add the H2O2 at sunset and allow the water to sit 24 hours before turning the pump back on. The tub or pool may be used afterwards.

It is NOT necessary to shock your pool or hot tub if you are starting with fresh water. H2O2 will not adversely interact with other pool chemicals.


This depends quite a bit on the water source and the amount of organic materials that enter the water (dust, leaves, number of people using the pool etc.) If you are starting with new water, a good starting point is 1 cup of 35% H2O2 for every 500 gallons of water.

H2O2 interacts with and oxidizes organic materials and decomposes with UV light. This is a reason that H2O2 must be added time to time to maintain its level in the water. There is no danger of H2O2 levels increasing or forming dangerous residual chemicals.


Peroxide test strips are a plastic strip with a reactive pad on one end. They are used to test the concentration of hydrogen peroxide in a solution. You can obtain these strips by doing a search on Google for “Hydrogen Peroxide Test Strips.” Ideally, you would keep the concentration level measuring between 50 and 100 ppm. For areas with high levels of organic contamination potential, this can be safely increased to as high as 1000 ppm. You can find test strips doing a Google search for “hydrogen peroxide test strips.”

NOTE: Be sure to check with your pool or spa manufacturer regarding H2O2 use on their equipment. Some systems have natural rubber which will be degraded by H2O2. More modern systems use a synthetic rubber which is not affected by H2O2.

CHECK YOUR FILTERS OFTEN: As with any pool or hot tub with a filtration system, you should regularly check your filter(s) as clogged filters will damage some pumping systems.

STORAGE: For best results, keep the H2O2 in a cool and dark place… either in a basement or frig. You can empty the gallon or 5 gallon bottles into 1 gallon or quart plastic containers and refrigerate or freeze them for optimum storage. UV light causes H2O2 to decompose.

CAUTION: wear plastic gloves and safety goggles when adding H2O2 to the water as it can splash or spill. You simply add the hydrogen peroxide to the water and no special injection system is necessary.


Some people will use a mix of the pool chemicals they have been using with hydrogen peroxide – and then reducing the amount of pool chemicals used. This is particularly true of commercial or public swimming pools (such as hotels, apartment complexes etc.) where the fear of the spread of disease is a major liability issue. Legal liability is not always about doing the right thing, but rather about doing the typical thing. For this reason, they want to be able to say honestly that they used the typical pool chemicals. This is a valid option. While a person should eat healthy meals 100% of the time, if not then why not eat healthy 50% of the time? Hydrogen peroxide will not have any reaction with pool chemicals. If in doubt or wanting to transition from chemicals to hydrogen peroxide, it is reasonable to reduce pool chemical usage by 1/3 and then use 1/3 the level of hydrogen peroxide treatment. If you like the results, go to 50/50 and so forth.

Another hybrid usage is that some people will blast their pool with chemicals the day (or night) before draining it, or almost completely drain it and add chemicals at that point, just in case the H2O2 was missing some contaminating factor. There is no reason not to do this if you wish. While a hybrid usage of hydrogen peroxide in a pool is a valid decision, it makes little sense in a spa – given how easily and inexpensively a spa can be drained. For a spa, we suggest trying 100% H2O2 treatment. However, you also can do a hybrid treatment if you wish. Maybe the most amazing part of using hydrogen peroxide for pool and spa treatment is the simplicity of it. It can not chemically build up in your pool. You do not have to continually be balancing chemicals against more chemicals to make it work. It does not require complex filters or machinery. It does not require exact levels of concentration to work. It bio-degrades completely to only healthy substances of water and oxygen – good for you and your pool/spa. It contains no toxins. You do not have to fear how it interacts with other chemicals. Nothing in hydrogen peroxide causes cancer, sterility, birth defects, brain damage, tumors, nervous system damage. It does not smell bad. Hydrogen peroxide for pool and spa usage does not produce toxic vapors. There is no complex transition to change to H2O2 for pool and spa treatment.