Algae spores are constantly entering your inground concrete pool, brought in by wind, rain, or even on contaminated pool cleaning tools or swimsuits. If the conditions are right, algae can bloom in just a few hours!
These conditions include
- Water that is not balanced correctly
- Warm temperatures
- Presence of nitrates, phosphates and/or carbon dioxide
- A lack of good circulation, filtration and sanitation is usually a contributing or primary cause of pool algae
Algae are living aquatic creatures that multiply rapidly on warm, sunny days. Containing Chlorophyll algae uses photosynthesis to grow, algae can grow in the sun or the shade, but most strains need at least a little light to be able to grow.
Algae also need food, and when it comes to an inground concrete swimming pool there is no shortage of food, nearly every speck of wind-blown dust feeds pool algae. Algae is always present in swimming pools, even crystal clear blue pools have microscopic algae content. It sits there waiting for the chance to bloom – this happens when the chlorine level dips and the pH rises, or the pump and filter of the pool are operating correctly.
What problems can algae cause?
- No one wants to go swimming
- To remove the algae requires time, effort and money
- Once you have experienced a large bloom, it becomes easier for more algae blooms to occur
- It can cloud and colour the water reducing depth perception of those using the pool
- While algae aren’t harmful to swimmers, it can harbour nasties such as E-coli bacteria
- It can clog up sanitation pathways in the water and clogs the pores in a pool filter
- It can hide in the crevices of a filter or in rough spots on pool plaster or tiles, behind pool lights and under ladder treads
- Algae can create a demand for chlorine in the water, consuming the chlorine that should be working on other pool contaminants.
- As it expels carbon dioxide, the pH level of pool water can rise.
Think of algae as like a weed in your garden – they are those unwanted pests that create more work for the gardener and sap up the nutrients from the plants we want to grow.
What types of algae are there?
There are over 21,000 known varieties, when it comes to pools algae is classified by its colour –
- Green Algae – this is the most common variety of algae and usually shows itself following a hazy condition of the water caused by insufficient sanitation or filtration. It floats freely in the water and sometimes cling to walls.
- Yellow Algae – clings to the sides of walls and is usually found on the shady side of a pool, it forms in sheets and can be very difficult to remove completely.
- Black Algae – it can be difficult to remove as it forms roots that attach to the sides of the pool and appears as black or dark blue or green *spots* on the water surface. If you don’t destroy the roots, a new *head* will grow back.