Algaecide, when used properly, can be an important tool in fighting the onset of green, black or mustard algae in your swimming pool. Algaecides are a liquid substance added to the surface of the pool. This chemical, however, can have side effects for both the water and swimmers if you add too much.
Algaecide is an optional pool chemical that many pool owners choose to include as part of their regular pool maintenance. The chemical is designed to prevent the onset of algae in your swimming pool. It can also be used to treat algae, but is more effective as a preventative tool. Add a dosage that corresponds with your pool's water capacity. It's important to know your pool's capacity in terms of gallons in order to correctly determine the dosage of algaecide required.
The presence of too much algaecide can lead to a foamy pool water. Small bubbles will begin to be produced as the water is pushed through the return jet and back into the pool. Do not confuse these bubbles and foam with another common problem, which is air in your pool lines. Air pockets within the filter system can cause bubbles on the pool surface as well. The bubbles and foam resulting from too much algaecide will be much smaller in size.
The amount by which you overdose the pool will determine how severe the resulting skin irritations will be. Swimmers inside a pool that has too much algaecide will witness an onset of eye and skin irritations. Other water chemistry imbalances can lead to eye irritation as well, including too much chlorine or unstable pH and alkalinity levels. The uncertainty of the cause of eye irritations makes it even more important to identify when you put too much algaecide in the water; otherwise, you may think the irritation is the result of other water chemistry issues.
Adding too much algaecide will have a counterproductive effect. The product will have a tougher time working when it's saturated in the water. There's not much to remedy an algaecide overdose except letting it naturally dissipate. Swimmer usage, evaporation and backwashing are all factors that can contribute to this. If you have sensitive skin and cannot wait until the chemical dissipates in the water, then you can always partially drain the swimming pool and add fresh water to dilute the algaecide.