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Tackling Metals and Algae in Your Pool/Spa

Tackling Metals and Algae in Your Pool/Spa

When my kids were growing up in the 90s, they loved watching Sesame Street on our local PBS channel (this was, of course, pre-cable).

I admit I also liked watching the show (even though I already knew my ABCs) because I grew up watching the Muppets. Still a big fan today. Some of my “friends” say I remind them of Fozzie Bear.


Green might be good for Kermit — but it’s not good for pools and spas. In fact, green (or any discoloration) is a sign of some potentially serious chemical issues going on in the water.

The general rule regarding discoloration goes like this: If the discoloration is clear, it’s usually a sign of metals (e.g., copper, iron, etc.) in the water. A murky/cloudy discoloration indicates the presence of algae (mustard/yellow, green, black, etc.). So, when I get technical calls and e-mails from service techs or homeowners that the water has a color to it, the first question I ask…“Is the color cloudy or clear?” How they answer the question defines my response.

If the discoloration is clear, then not only do we need to find the source of the metals, but we also need to treat the water to remove them. Metals come from a variety of sources and are present in trace amounts in all pool water. They are not problematic unless they come out of solution. These metals usually come from two sources: (1) well water used to fill the pool (2) heated pool water that is corrosive and eats away at the heating element, which is comprised of copper. Ridding the water of metals is easy using one of the many sequestering/chelating products available on the market today.

If the discoloration is cloudy or murky, then you’re likely dealing with algae. Prudent use of algaecides/algaestats will solve that problem. Worst-case scenario is the need to do a 30 ppm algae shock with a lot of brushing (sometimes the cure is worse than the disease!).

And remember, water should be clear — NOT blue, green, purple or any other color. I love it when callers say, “My pool water is blue, and that’s a good thing.” Um…that’s only if the water is clear and is just reflecting the color of the paint or the vinyl or fiberglass shell.

Kermit is green. Fozzie Bear is brown. Cookie Monster is blue. Elmo is red. Big Bird is yellow. And that’s where the colors should stay!