Letter to the Editor – Pink Slime
To those lucky enough to own a swimming pool may know Pink Slime, it is often called Pink Algae. It is not actually an Algae but a Alphaprobacteria or naturally occurring harmless bacteria present in the air and all around us, in particular the inside of your garden hose and once your pool is infected it’s the devil’s own job to eradicate.
It has infected my pool twice before in previous years and twice this year, first in April when I was able to control it but didn’t actually rid the pool of it until June and it appeared again about two weeks ago. Probably as a result of all the rain we have been having this year.
It first appears as a pink coloured slime which attaches itself over everything in the pool, tiles, grout, seats and any shaded areas or where water movement is slack. It particularly loves PVC piping and is why it is such a pest to eradicate. If left it will completely choke your skimmer and pump baskets in a clinging mass of jelly like matter and eventually the main filter where it can lurk for ages. The first indication of its presents will be a sharp increase in chlorine consumption. For example to maintain a good water chemical balance in my pool of 60,000L around one and a half to two 200g multi-function chlorine tables per week are consumed. With the presents of pink slime this will increase rapidly to six or seven tablets a week.
If you look closely you will first notice brittle black threads of matter in all the sharp corners of the pool which is a breakup of the bacteria matrix before it takes a hold and mixes with fine dust in the pool. This stage is soon followed by small sheets of very fine pink gossamer slightly more dense that water which when disturbed and detaches from its host swirl around in the water movement eventually settling to the bottom of the pool.
I have found the only sure and effective way to rid the pool is as follows but it does work. Take a stiff brush or broom and scrub every square cm of the pool surface area, if you can get behind the pool lights so much the better. Dose the pool with 1kg of chlorine of granules per 20,000L of water and leave the pump running for at least 24 hours and also run the Jacuzzi pump and blower if you have one. Once dead the pink slime will take on a gray colour and cover the pool floor. Vacuum it up and thoroughly backwash and rinse the filter, backwash again the next day and add a fluctuant jell or equivalent to the pump basket and backwash again in 7 days. It will be at least a week of strong sun shine before the chlorine returns to safe or normal levels before using the pool.
Good Luck!! Ginger Marks.