You or your technician have been maintaining your pool regularly but there is this one week in summer when your pool didn’t get service and next thing you know you got a green pool.
Alga is the culprit, a one cell microorganism that can reproduce rapidly if given what it needs to prosper: water, sun, air, nitrates and phosphates. Here we are going to talk about phosphates, which are basically algae food.
But how did phosphates get into your pool in the first place? They are constantly being introduced into your pool water because they are found in decaying vegetation, fertilizers, municipal water, cosmetics used by bathers and even pool chemicals.
On top of the fact that phosphates are constantly entering your pool water you also have to take into consideration that there are thousands of different species of algae, and they all differ in the amount of phosphate they consume. So a phosphate level that would starve one type of algae will provide perfect nutrition to another.
Even if you reduce phosphate levels with a phosphate remover to below 20 parts per billion, there are several species of algae that are know to have optimum ranges even at that low phosphate level.
Then there is the fact that algae have the ability to store phosphorus within their cells, which basically means that even if you starve the algae, like chubby humans denied food, those algae can live for a while off their stored phosphate.
Prevention is the key to avoiding this type of problem. Make sure your pool has optimum chemical levels that prevent algae growth. Your pool should get tested and treated every week of the year, especially in the warmer months.
But what to do if you already have a green pool? There are several approaches: you can use an algaecide to kill the algae and then vacuum the dead algae from the pool, you can shock the pool with chlorine, or you can do both methods, it will all depend on the type of algae that has grown in your pool. Your pool technician should be able to solve the problem. If not you need to call us.