Avoiding Algae in Swimming Pools
Many poolowners frequently fight algae; this guide may help you with stay out
of the battle!
The Primary Causes of Swimming Pool Algae
All sorts of possible causes of algae are detailed here, and in the connected
pages. But, the most problems with algae can be related to a few things. (This
discussion relates primarily to chlorine pools)
- Failure to maintain adequate levels of chlorine.
- Stabilizer buildup from use of dichlor, combo shocks, trichlor based shocks and the like.
- Nitrogen buildup or other chlorine consuming/defeating build up from combo shocks, cheap algaecides, clarifiers and the like.
With respect to many swimming pool chemicals sold today, less is more. The less you use, the better your pool will run.
Every time you add something to your pool that you didn't really need, you increase your risk of problems of all types.
Today's pool chemical company marketing programs are dedicated to convincing you that more is more. And, they are right: more chemicals means more money for them, and more problems for you . . . which leads to more money for them.
But, the bottom line is that you'll never escape from the cycle of dependence on the products the pool chemical companies want to sell you, and the problems caused by those products . . . unless you learn to test and manage your own pool's chemistry. The entire pool chemical testing/computer analysis/'custom dosing chart' package is designed with one overarching purpose in mind: to make certain you leave the store with an armful of chemicals.
Until you are ready to learn to test and manage it yourself,
you'll remain the pool chemical companies' victim.
Steps Toward AVOIDING Swimming Pool Algae
Swimming Pool Algae AVOIDANCE Steps for ALL Pools
- Maintain adequate basic chemical levels (chlorine/bromine or PHMB or copper).
- Never use a chemical product you don't really need.
- Purchase and USE a test kit for the sanitizer/oxidizer/algaecide
you are using.
- Shock appropriately, in the evening, not in the morning.
- Run your pump at least 6 hours per day in TWO different periods.
- Brush the ENTIRE pool at least once every two weeks during the swim season.
- Do NOT use the cheap foamy algaecides (gallon jugs!).
- Keep your pH between 7 and 8.
- If available, use borax, not baking soda or soda ash, to raise your pH as
Swimming Pool Algae AVOIDANCE Steps for Brominated Pools
- Drain and replace 1/4 to 1/3 of your pool's water every spring, to lower
built up levels of dimethyl hydantoin, the chemical carrier used in solid
forms of bromine.
- Instead, consider the weekly use of a polyquat
- If you shock, make SURE you do so in late evening.
Steps for PHMB Pools (Baquacil, SoftSwim, PolyClear, etc.)
- Buy and use a good test kit, though I can't tell you where to get one! But you can't
maintain a pool unless you know what's in it.
- Drain and replace as much as possible of your pool's water every spring, to lower built
up levels of PHMB residue.
- Inspect your sand filter, DE filter internals, or cartridge EVERY SINGLE YEAR! PHMB is
notorious for ruining filter media. While the special PHMB compatible filter cleaner can
help, it doesn't solve the problem. In most cases, you'll need to replace filter media
every year. Poorly functioning filters are a common cause of insoluble pool problems on
- Test and maintain adequate hydrogen peroxide shock levels. Hydrogen peroxide is removed
by sunlight, just like chlorine is.
Steps for Copper Treated Pools (Nature2, Ionizers, Pristine Blue, etc.)
- Buy and USE a good copper test kit, and maintain appropriate levels of
- Keep your alkalinity and calcium as low as possible. Both inhibit copper's algaecidal
- Using stain control agents tend to prevent copper from being effective.
- Algae is what copper is good at killing. Some of the other claims, well, they are . .
. claims. But if you have algae on a copper treated pool, your copper treatment may not be
- If you get algae anyway, make sure your copper level is BELOW 300ppb (0.3ppm)
before shocking. Otherwise, you may get staining.