What is Algaecide?
Algaecide in the purest meaning is anything that prevents or kills algae. In the pool chemicalsworld, algaecide comes in three different varieties – quaternary, polyquats and copper-based.
These chemicals act by disrupting energy transport, cell division, or the cell membranes which allow the algae to become more vulnerable to sanitizers such as chlorine. Each type of algaecide is different and is more or less effective depending on the type of algae it is used to prevent or kill.
What Form(s) Does Algaecide Come In And How Do I Use It?
Quaternary (quats)
Quaternary ammonium compounds come in liquid form and are typically sold in quart sized bottles and should be poured around the perimeter. They are mostly used for algae prevention vs killing.
Pros of Quats
- Cheaper than Poly quats or metal-based
- Does not add metals to your water
Cons of Quats
- Causes water to foam
- Can have a chemical smell if overused
Poly Quats
Poly Quats are polymeric quaternary ammonium compounds and come in liquid form, typically sold in quart sized bottles and should be poured around the perimeter. They are mostly used for getting rid of algae vs prevention of algae.
Pros of Poly Quats
- Lasts longer
- Does not cause foaming
- Does not add metals to your water
- Twice as effective as quats
Cons of Poly Quats
- Most expensive
Copper-based
Copper-based algaecides contain copper ions and come in the form of liquid to be poured around the perimeter or solid mineral for adding to your skimmer. They are used for prevention and killing of algae.
Pros of copper-based
- Works well on black algae
- The solid mineral form is easy to handle and administer
Cons of copper-based
- Increased risk of staining for plaster pools and plastic steps where fill water may already contain copper ions
- Can cause blonde hair to turn green
Safety Information about algaecide
Algaecide is not a reactive chemical like others used to balance water chemistry and can be easily and safely added to your pool (or spa). Always read the manufacturer’s instructions for application and storage.
Interesting Fact About Algae
Algae are in your kitchen and bathroom. Listed as carrageenan or alginate, you’ll find them in ice cream where they prevent ice crystals from forming, in chocolate milk to keep cocoa suspended, and in salad dressing to keep the components mixed. Algae gel your toothpaste, thicken your body lotion, and coat tablets to hold the ingredients together. (source)