Mustard yellow algae are tough to recognize and eliminate from the pool. You must eliminate mustard algae in the pool as soon as possible because it can be dangerous for humans. The longer you wait, the longer it will take harsh chemicals, far more than bleach, and hours of cleaning to remove the mustard-yellow algae.
How to recognize mustard yellow algae in the pool?
Mustard yellow algae are difficult to recognize in the pool. It can often be confused with pollen floating on the surface or a small sand pile at the bottom.
Yellow algae are very thin, like a powder. As soon as the water moves next to it, it disappears and seems to dissolve into the water. When the robot passes, or when there is someone in the water, it is often invisible. To observe it, wait 3 hours after the end of the filtration while the water rests. If you see yellow spots at the bottom of the water, it’s mustard yellow algae!
Mustard yellow algae are very resistant, especially to chlorine. Much more resistant than green algae. See here the method to clean a green pool.
What causes yellow algae in a pool?
In scorching areas, mustard yellow algae often arrive by the wind. When you detect mustard algae in the pool, your neighbors certainly will also.
Yellow algae usually develop when there is a lack of filtration and chlorine in the pool.
Is mustard algae dangerous for humans in the pool?
The mustard yellow algae in the pool are not particularly dangerous for humans. However, it is recommended not to swim when algae are in the pool. They can harbor other hazardous bacteria.
Get rid of mustard-yellow algae in the pool
The procedure for getting rid of mustard yellow algae is the same as for the algae, only more substantial. Green algae are very easy to eliminate compared to yellow algae. Please do not panic. It will come to an end anyway.
- Machine wash all swimsuits. The mustard yellow algae attach itself everywhere and survive out of water. There is a risk that a piece of mustard algae remains on a swimsuit and re-contaminates the entire pool. That’s why you have to start by washing the swimsuits.
- Clean all accessories and games with bleach. Do not forget to dilute the bleach a little. For example, 1 part bleach for 10 parts water. Pure, it could damage certain plastics or rubber. As with bathing suits, the mustard algae could cling to the broom, the buoy, a floating analyzer, etc. That’s why everything has to be cleaned by hand.
- Place all large equipment in the water at the shallowest point. The mustard yellow algae could cling to the pool robot or vacuum cleaner. Any equipment that is too difficult to clean by hand should be put in the water to be treated with the pool.
- Brush the pool, the walls, and the bottom. If possible, use a stiff broom on concrete or tiled pools. Keep a broom with a soft brush on vinyl liner pools because the metal bristles damage the coating. You can then vacuum to manually catch and reject as many algae as possible. Go everywhere, including the skimmer and the steps above the water line.
- Clean the pool area. For example, pass the Karcher over the copings.
- Wash the filter. The mustard yellow algae can become lodged in the swimming pool’s sand filter. Backwash the filter to eliminate it.
- Balance the water. Check and adjust TA, pH, sanitizer, and stabilizer.
- Perform a Chlorine Shock, or super chlorination, at a double or triple dose. The mustard yellow algae are very resistant, so you must use even more chlorine to eliminate them. Let the filtration run for at least 24 hours afterward.
- Maintain a high level of disinfection for several days. The idea is to prevent the mustard yellow algae from settling back into the pond as much as possible.
- Brush the pool, the walls, and the bottom, again. Mustard algae are tenacious!
- Shock chlorine again, and leave the filtration on for 24 hours afterward.
- Test and re-adjust the water balance.
If no mustard yellow algae appear in the following days, it’s won! You can remove the equipment from the water before the treatment and enjoy the pool again.
How do you know when mustard yellow algae are dead?
Knowing when the mustard yellow algae are dead and eliminated from the pool takes patience. The only way to be sure it has been destroyed is to check the pool regularly for a week. If the water remains balanced, with a good level of pH and disinfectant, and there is no yellow trace, it is a sign that the yellow mustard algae are dead.
Copper sulfate to eliminate mustard algae?
Copper sulfate is used to kill algae, including mustard algae: it is a powerful algaecide. It is also a hazardous product, toxic for humans and the environment.
A copper sulfate algaecide can be used in small quantities, as indicated by the Government of Canada.
Copper sulfate never leaves the pool. It stays forever in the water. Using too much copper sulfate can make the pool dangerous for humans or even turn green.
Baking soda is helpful for many things, including in the pool, but is useless for mustard algae.
You can use diluted bleach to remove mustard algae from pool accessories and games. Bleach is not powerful enough to kill the mustard algae in the pool. You must use a more concentrated product like a quick-dissolving shock chlorine tablet.
The natural method to eliminate mustard algae is not very economical. You must empty the pool (which can damage it), clean the pool and all the equipment and accessories with bleach, and let it dry. You can then fill the pool again.
A high quantity of chlorine kills mustard algae in a swimming pool. You must use two or three times the doses you usually use when shocking the pool.