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How to Remove Algae From a Salt Water Pool

When it comes to swimming pools, some people prefer salt-chlorinated water over a regular chlorine pool for its supposedly gentler effect on skin and eyes, but otherwise you will find there to be very little difference.

While saltwater pools have their benefits, there are some situations when good old-fashioned chlorine is simply the only answer- finding algae in the water is certainly one of these times. You may ask, ‘Won’t adding chlorine to my salt pool damage it and ruin the levels?’, but no, not when algae has reared its ugly head and is spoiling the fun.

How to Remove Algae From a Salt Water Pool

The usual trick of switching your saltwater system to the ‘super chlorination’ setting may not be enough to defeat the pesky green invaders, even if you have been doing this every month, which is recommended for general upkeep of your swimming pool.

The most effective way to clear bacteria from the water is pool shock treatment which you might need to apply more than once depending on the severity of your algae situation.


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Related Post: Pool Salt Calculator

Finding algae in your pool can certainly be unsettling but don’t worry. With a little bit of care and effort you can easily get things back to looking how they should. There are a few things you will need to have on hand to complete the job successfully by yourself:

1. Water test strips: They will show you the water’s current PH balance as well as the alkalinity level. If you are not confident about how to check and read levels properly by yourself, you can take a water sample to a pool supply store and they can check it for you.

2. PH increaser/ Ph decreaser: If your levels are not where they should be, you can balance them out by adding the necessary chemicals. Don’t forget to check again to be sure they are correct.

3. Alkalinity increaser: Again, you will only need this if the alkalinity level is too low- something you want to avoid as it can lead to your pool surfaces suffering damage, along with anyone who goes into the water.

4. A good pool brush: Giving the walls and floor of your pool a good scrub before treating the water will make it easier for the pool shock to attack the algae spores.

5. Pool shock: This is the MVP of the process and it’s important to use the correct amount. When using the standard calcium hypochlorite shock, the recommended dosage is 1 pound of shock per 10,000 gallons of water, but since we are trying to clear already existing algae, you are going to want to double up at the very least.

To sum that up, if your pool is 10,000 gallons or less you should add a minimum of 2 pounds of shock treatment to the water. Pool shock is much better value for money when you buy in bulk, so if you don’t already have some stocked up, think about going down this road so you have it handy whenever you need it to avoid any major algae build ups over time. It will also be useful if you end up needed to repeat the process.

When you have everything prepared and ready to get the ball rolling, following these simple steps will optimize your chances for perfect swimming conditions as soon as possible.

Step 1: Test the water levels and balance accordingly.

Take your test strips if you are going fully DIY, or collect your sample if not, and check the chemical balance of the water. The levels you want to see are between 7.4 – 7.6 PH, and alkalinity of anywhere between 120 ppm and 150 ppm (parts per million), so if necessary, take your PH increaser or decreaser and your alkalinity increaser and add accordingly.

Shock treatment is at its most effective when everything is balanced as it should be, so taking the time to get this right will give the pool shock treatment a head start and is definitely worth it.

Step 2: Clean the pool surfaces.

The more effort you put in now, the better the end result will be. It’s harder to kill algae when it ‘s still clinging to a surface, so focus extra effort on the tricky spots like corners, beneath ledges and behind ladders where grime is most likely to gather.

Step 3: Decide how many doses of Pool Shock to use.

The best way to decide how much to use is to base it on the color of your water. As I said before, a minimum of 2 doses (a single dose being 1 pound per 10,000 gallons) should be used, if your pool is a light green shade.

If the water is dark green, consider a triple dose. Lastly, if your pool has been neglected for a while and you are facing water that looks almost black, a quadruple dose will be needed, and you may need to shock it more than once.

Step 4: Shock the pool.

After determining the dosage, the next step is to apply. Timing is everything- don’t shock your pool in the middle of the day or the sun could burn it off before it has a chance to work. The best time is in the evening. You can apply the treatment then leave your pump running for 8 hours overnight to fully circulate the shock treatment.

Step 5: Check the color.

The following morning, if the process worked, your water should be cloudy blue. The cloudy effect is the dead algae, which your filter will clear. If, however, the water still looks green, you should repeat the shocking process that same night.

If your pool is still green after two nights of treatment, there could be some underlying issues. Make sure your filter is running consistently through the process then get your water tested and your pool checked by a professional. Assuming the process worked and the water is cloudy blue, your pool is now safe to swim in. Run your filter constantly until the water is completely clear and you are done!

Now your pool is looking pretty again, the next question is: How do I keep it that way?
It all comes down to regular basic maintenance. A little TLC goes a long way and will help avoid any major issues further down the line. Brushing, vacuuming and cleaning the walls, floor and accessories on a regular basis will make it hard for algae spores to settle. Running your pump and filter 8 – 12 hours a day keeps the water flowing and gives algae a lot fewer chances to take over.

The most important factor is keeping the water sanitized and perfectly balanced. Without the proper chemical levels all kinds of things can go wrong. Get into a routine of testing thoroughly and regularly so things don’t get out of hand. If your pool is especially prone to algae, you can even shock your pool weekly with a single dose of treatment for peace of mind.

Like so many things, the condition of your swimming pool will thrive with simple, regular care. Leaving it to its own devices for weeks or even months on end will only bring you trouble, costing precious time and potentially a lot of money.

Going for a swim on a hot, sunny afternoon is one of life’s greatest pleasures, but green algae infested water does not fit in with our summer dreams. With a bit of patience and a little elbow grease, you can clear the offending grime and get back to relaxing- but you can avoid it all together by keeping up your regular maintenance routine.

Algae From a Salt Water Pool
Algae From a Salt Water Pool

About the author

Hi I’m Alex, founder of HouseholdMe.com and I’d like to say thank you for dropping by. Like most of you, the first thing I look at before buying something online is reviews or buying guides. By reading what other people say will help me gauge whether or not a product is good or not.  I am trying to help people find answers, solve problems, and get inspired.

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