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A Glossary of Important Pool Maintenance Terms: Part I

Acid. It might seem odd, but if your pool’s pH balance is off (see pH) you’ll need to add acid to your pool. Acid is a chemical that contains hydrogen, and can balance out the presence of alkaline materials in your pool. But beware: Too much acid, and your pool water can corrode metal and be uncomfortable to swim in.

Air Relief Valve. On top of your filter’s tank, there’s a valve that regulates the air pressure inside the filter. Turning this valve relieves the pressure inside the filter.

Algae. Algae is a scientific catch-all term for a variety of microscopic organisms that have features similar to plants. They’re fairly harmless, but they can drastically change the color of your pool water, and if algae gets thick enough, it can damage your filter.

Algaecide. As its name implies, algaecide is a substance you use to kill algae in your pool. These might be herbicides, or they might be silver or copper compounds. Each type of algaecide tackles a different type of algae, so be sure you know what kind of algae you have before heading to the pool supply store.

Alkalinity. The opposite of acidity, this is often referred to as total alkalinity. You can find out your pool’s by testing its pH; you can do this with test strips you find at your local pool supply store.

Apco. Apco is the finest name in pool service and pool maintenance. We serve the greater Delaware Valley and offer a variety of services. We also sell pool components like pool covers and vinyl pool liners.

Backwashing. Specifically, this refers to the process of reversing the flow of water through your pool’s filter in order to clean it.

Bleach. This is another term for liquid chlorine; it’s similar to the bleach used in cleaning laundry, but pool bleach has about three times the concentration of actual chlorine.

Calcium Chloride. This is a water-soluble white salt that can be used to alter the hardness of your pool’s water.

Calcium Hardness. This term describes the calcium content of your pool water; your water can be either too “hard,” or not hard enough. If it’s too hard, the water will be uncomfortable to swim in, and white calcium buildup may appear on your fixtures. Not hard enough, and the water may corrode metals.

Cartridge Filter. There are multiple types of pool filter; a cartridge is the replaceable element of your filter, and it’s generally made of polyester or paper.

Chloramines. If you don’t have enough chlorine in your pool, the unpleasant compounds the chlorine is meant to destroy will only partially break down. When this happens, chloramines are created, which can smell bad (oddly, they have a strong chlorine smell) and make swimming unpleasant.

Chlorine. A material used to disinfect swimming pool water, what we commonly refer to as chlorine is often sodium hypochlorite.

Clarity. This term describes the transparency of your pool water. If your water is not clear, it may be a sign that you have an algae problem.

Cover. A pool cover is meant to protect your pool when it’s not being used.

Diatomaceous Earth (also known as DE). DE is a powder that’s made up of thousands of fossilized diatoms, or single-celled organisms. Because the tiny fossils are porous, they make a perfect material for filtering impurities out of your pool water. DE filters are some of the most effective pool filters on the market.

Drain, or Main Drain. Situated in the deepest part of your pool, the main drain is connected to your pool’s pump so the water is circulated and filtered.

Filter. Your pool filter’s job is to keep the water as clean and free from unhealthy particles as possible. It cleans the water by running it through a porous substance that pulls impurities out — a substance like sand or diatomaceous earth.

Filtration Rate. This term describes the speed at which water moves through your pool’s filter.

Hard Water. Water is considered “hard” when it has unacceptably high levels of calcium or magnesium. Hard water can result in less-than-pleasant swimming conditions and a crumbly white buildup on pool fixtures.

Inlet. After your filter cleans your pool water, it passes it back into your pool via the inlet.

Leaf Net, or Skimmer. You’ve probably seen one of these tools even if you don’t own a pool yet. It’s a net situated at the end of a long pole, used for plucking leaf litter or other floating debris out of the pool.

Liner. Vinyl pool liners are meant to hold the water in your pool and protect its walls. Pool liners should always be in good working order, and free of any rips or holes, so your pool walls and floor aren’t broken down

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