The Magic of Minerals and Metals
There are a lot of things that get into pools that we need to treat. At the same time, we add a lot of things to the pool as treatments. What is especially interesting is that minerals and metals fall into both of those categories. It is a unique feature that these can be both beneficial and harmful to pools. The key is to understand how they can help or hurt your pool to get a benefit or avoid a problem.
Mmmm, Is it a Mineral or a Metal?
Metals and minerals are not the same, but they are closely related. According to the US Geological Survey, a mineral is a naturally occurring, inorganic solid with a specific chemical composition and crystalline structure. Metals, on the other hand, are a class of elements known for being shiny and conducting heat and electricity. While closely related, they do differ. Minerals are naturally occurring compounds and metals are elemental materials. The ones in pools we need to be aware of include copper, silver, iron, and manganese.
Minerals and Metals, Oh My!
We all strive for sparkling, crystal blue water, but we know sometimes our pool water can take on different hues. When there are oxidized metals in the water, it can lead to colored water or staining. The most common colors include green, red, brown, and black. Minerals and metals can get into our pool water through our fill water, chemicals used in landscaping around the pool, specialty treatment chemicals, poor water chemistry, older pools with iron or copper pipes, corroded heaters, or even adding them directly to the pool to treat our water.
Maximizing Metals and Minerals
While we prefer to get metals and minerals out of the pool, some do add them to the pool to help treat their water. Copper algaecides and silver sanitizes, so it can be used as a supplemental water treatment system. However, by knowingly adding metals and minerals, water chemistry needs to be vigilantly maintained; otherwise, staining can occur.
When we see brown or red water or stains, it is a sign of iron or manganese. Their presence can lead to corrosive water conditions that can dissolve pool walls and metal components in and on the pool, including handrails, ladders, light fixtures, heater components, and pump impellers. When we see green or blue-green water, it is typically from algae. However, in the metal and mineral world, it is the presence of copper. When this is the case, we need to be sure to avoid adding high levels of oxidizers (chlorine), or increasing the total alkalinity can cause these metals to stain surfaces.
Hmmm, what to do with minerals and metals?
Since chlorine performs the best sanitizing and oxidizing capability for our pool, utilizing a secondary system that does what it can do and increases the chances of surface staining, we do not recommend using these systems. We do encourage testing for metals and testing your fill water so we know exactly what we are adding to the pool when we add water. It is especially important to be careful if you fill with well water. If you inadvertently get metals or minerals into your pool water, you can remove the minerals and metals through sequestering and chelating agents to prevent staining. These products will break down minerals and metals to combine with those metal ions in the water. We can then remove them with assistance from the filter and vacuuming. We want to remove the metals and minerals before staining, as it is easier than treating the stain.
