How to treat mustard algae in your pool ?

The swimming pool has its enemies, some are more formidable than others. It is in any case the case of the mustard algae that it is absolutely necessary eliminate, but let’s face it, it’s not as easy as it seems. Let’s find out what exactly this rather tough algae is that can pollute all swimming pools of the same area, and which gives the bathing water this yellowish color. Let’s also see what are the best solutions to eradicate it.

What is mustard algae?

Mustard seaweed is ocher in color, which is why it is also calledyellow algae. She looks like a poudre very fineextremely volatile. The wind from the Sahara easily carries its germs with the dust and spreads them on its way. This is how this mustard algae settles in swimming pools, especially those built in areas exposed to this type of wind.

The problem is that the anti-algae treatments that we use regularly have no no effect on mustard algae. In addition, its high volatility prevents it from being sucked up by swimming pool robots which only lift it, and it then redeposits on the bottom but also on the walls of the pool. This algae is most apparent when the water is not moving. We can therefore think that it has disappeared when we pass the vacuum cleaner for example or when we bathe, but it is not so: it reappears afterwards.

Get rid of the mustard algae that invades the pool: the radical solution

It is essential to identify the algae that is invading the swimming pool because there are different species, and the treatments must imperatively be adapted. However, you don’t need to be a proven botanist since it is by their color that you can tell them apart. Green, brown, blackā€¦ and ocher yellow for mustard algae, reputed to be the most resistant there is by swimming pool specialists. If certain algae are easily treated, this is indeed the case with yellow algae which, in addition, automatically contaminates all swimming pools located in the same geographical area, more or less extensive, when it is very exposed. to south winds.

The single treatment which makes it possible to overcome it is a specific product against mustard algae au bromide salt. It costs on average 22 euros per kg. But it is only under oxidation that the bromide salt becomes active. This yellow anti-algae must therefore be used imperatively with disinfectant so that it is oxidized. It can be bromine, active oxygen or chlorine for example.

Attention, before processing, we start with check pH pool water. For the treatment to take effect, this Hydrogen potential must absolutely be correct. If this is not the case, it should be rectified first.

Care must be taken to scrupulously respect the dosages clearly indicated on the packaging by the manufacturer. Some recommend for an initial treatment 30 g of mustard anti-algae for 10 m3 of water and for a curative treatment 1.25 liters for 50 m3 of water but on condition that this product is associated with a shock treatment. This decontamination implies that the walls and bottom are rubbed so that the germs are detached, and it is necessary to let the filtration system run for at least 48 hours without stopping.

The bathing must be prohibited during the hours following treatment with Mustard algae stopper. It is necessary to wait until the water has become healthy and clear again. If it is still a little cloudy, you can use a flocculant sock so that the turbidity disappears.

Mustard algae being tough, it is necessary to two water treatmentsto take advantage of it decontaminate also all objects (inflatable mattresses, swimming games and toys, buoys, etc.), pool equipment, cleaning the surroundings. Then we carry out during the season at least two or three preventive treatments, or even more if one is installed in a region where the winds are frequent and where it rains frequently. This is absolutely essential to avoid recurrences.

Photo credit: Boris Drenec

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