Water Chemistry

Phosphates and Algae Food, Explained

A pool can have perfect chlorine and pH and still grow algae fast, and phosphates are usually why. This site is built around the high end of what gunite construction allows: negative/infinity edges, swim-up bars, sun shelves, fire-and-water features, and full outdoor-living integration with decking, kitchens, and shade structures designed alongside the pool, not as an afterthought.

Gunite pool under construction, shell and decking

Algae's Fertilizer

Phosphates enter pool water from fertilizer runoff, decaying leaves, certain tap water sources, and even some pool chemicals themselves. They don't sanitize or harm swimmers directly, but they function as a nutrient source that lets algae grow faster than a given chlorine level can keep up with.

Testing and Reducing Phosphates

A phosphate test kit (separate from a standard chlorine/pH kit) is the only way to know the level; a phosphate remover product can bring it down, but it treats a symptom, keeping yard debris and fertilizer runoff out of the pool in the first place reduces how often that treatment is needed.