So, you were admiring your pool, and suddenly, you saw something yellow in the water, looking like… mustard? Wait, mustard? Was anyone eating hotdogs in the pool?
While that might be the case, the most likely culprit is yellow algae, or what we also call mustard algae. While a yellow pool and some algae seem harmless, they can wreak havoc all over your pool surface, water quality, and equipment if left untreated.
If your pool is yellow, read on to find out how to get rid of it!
What is Mustard Algae?
Mustard algae, or yellow algae, is a member of the xanthophytes, a microbe family, and another form of green algae.
Mustard algae likes to attach itself to your pool walls, among other things, which causes a more significant problem because that means it can survive outside swimming pools. This ugly yellow blob can stick to floaties, pool toys, equipment, and bathing suits!
You’re probably wondering: Why is my pool yellow, and where does mustard algae come from?
There are different reasons why mustard algae visits your pool and surrounding area.
- It can come from contaminated swimsuits or equipment.
- Algae appears in your pool overnight from harsh rains and winds
- You live in a place with a warm temperature or currently experience warm sunny days
- You have imbalanced water chemical levels, or the pool water contains carbon dioxide or nitrates. Usually, poor pool care, such as poor sanitation, filtration, or circulation, causes mustard algae.
Now that you know what mustard algae is, what does yellow algae really look like in my pool?
Unlike green algae, yellow algae aren’t slimy and would vary in color slightly, appearing yellowish, yellow-brown, or yellow-green. Because of the un-algae texture, yellow algae is usually mistaken for dirt, stain, or sand in the pool.
You can distinguish between dirt or pollen and algae because the latter has a slimier feel than a gritty one. Usually, you can see yellow stains on pool wall or algae spots on pool floors. As time goes by, algae will grow in larger clumps if left untreated.
Algae itself isn’t dangerous to humans, but an overgrowth may harbor harmful bacteria that become dangerous, like E. coli. Furthermore, algae can stain the swimming pool and cloud pool water. No one wants to look or swim in all that yellow stuff!
Furthermore, filters can become clogged by mustard algae. As a result, the filters cannot correctly clean pool water. Moreover, the algae will absorb chlorine, which reduces the amount required to fight contaminants away.
How to Treat a Yellow Pool
These nasty yellow things are chlorine-resistant and very persistent, so it can take a bit of elbow grease and products to remove algae.
Fortunately, you can do things for yellow algae removal to prevent it from showing up again.
Here are the steps to follow on how to get rid of yellow algae in pool:
- Wash all your bathing suits using a washing machine, then dry them with a dryer, killing algae if they were infected.
- Disinfect all the pool toys and floaties using a chlorine-based solution. You can also use Clorox cleaner, which works just fine. Do NOT use the Clorox bleach, as you wouldn’t want to bleach the pool toys!
- If there is one, place all of your pool maintenance equipment, like your poles and hoses, to the shallow end of the pool. When treating the pool with shock will also sanitize your equipment. But if some of your equipment was already infected with mustard algae, it’s best to dispose of it to prevent the algae from spreading. Make sure you scrub your pool filters at this time, backwashing sand or D.E. filters if you won them.
- Fill your pool with fresh water. Use your manual vacuum cleaner (NOT an automatic vacuum), turning the filter to waste rather than backwash.
- After cleaning the pool with a vacuum cleaner, have it tested to ensure that you have properly balanced water. The pH levels need to be 7.4 to 7.6, with alkalinity levels being 120 to 150 parts per million (ppm). Such levels will have the shock treatment become even more effective.
- Brush algae off the pool floor and walls with a pool brush. Make sure you brush all parts of the swimming pool to break up algae and have it float for the chlorine from shock to attack and destroy them.
- Shock all that algae away! Use 1.5 kilograms for every 40,000 liters of water. We recommend shocking the pool during the evening or dusk, leaving the pool pump and filter running 24 hours a day until there are no more signs of algae.
- Continue to brush the swimming pool for the next few days and keep it appropriately sanitized. Also, monitor the alkalinity and pH levels to ensure they remain in the acceptable range. The algae should NOT attach itself to anything around the pool to be easier to kill.
- After a few days, once it seems you destroy all algae, it’s best to shock it one more time, using one pound for every 10,000 gallons. Test the water and repeat the steps until the water chemistry is good and your pool water remains clear.
Prevent Yellow Pool from Happening
Now that you know what yellow algae treatment for pool to follow, here are ways to prevent it from happening again:
- Constantly keep the alkalinity, sanitizer, and alkalinity levels in proper ranges all the time.
- Run the pool pump and filter 8-12 hours a day.
- Keep the pool clean by brushing and vacuuming regularly.
- Shock your pool weekly, using one pound for every 10,000 gallons of pool water.
- Make sure that you keep all your pool equipment clean, such as your floaties, pool toys, steps, ladders, slides, diving boards, pool covers, or solar blankets.
- Stock up on yellow algae remover or an algaecide to both get rid of and prevent mustard algae altogether.
Wrapping It Up
The next time your pool is yellow, you know what to do! As long as you’ve got the right equipment and products, you won’t have to worry about that nasty yellow stuff floating around your pool and water anymore.