Phosphate
A nutrient compound in pool water that can fuel algae growth.
Definition
Phosphates are compounds containing phosphorus (PO4³⁻) that enter pool water from bather waste, lawn fertilizer runoff, fill water, and certain pool chemicals. Phosphates are a primary nutrient for algae. While low phosphate levels alone do not cause algae (chlorine control is paramount), very high phosphate levels (above 500–1,000 ppb) can reduce chlorine effectiveness and increase algae risk. Phosphate removers are available but their necessity is debated — good chlorine management prevents algae regardless of phosphate level.
Quick Facts
- Ideal Range
- Below 200 ppb (ideally)
- Units
- ppb
- Also Known As
- PO4, phosphate, phosphates, phosphorus
Relationships
Incoming Relationships
- affected by ← Algae