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Chemistry Chemistry

ORP (Oxidation-Reduction Potential)

A measure of the waters oxidising vs reducing chemistry - reef tanks target 300-400 mV; lower indicates organic buildup, higher indicates strong oxidising conditions.

Unit: mV Code: ORP

📊 Ideal Ranges

Reef
300-400 mV

📖 Overview

ORP quantifies the electrochemical potential of water to oxidise or reduce contaminants. Fresh, well-oxygenated water has high ORP (300-450 mV). Water saturated with dissolved organics has low ORP (below 200 mV). Ozone treatment raises ORP dramatically - potentially damaging livestock at over 500 mV. Aquarium controllers monitor ORP to safely regulate ozone injection.

🧪 Testing Methods

ORP probe on aquarium controller. Handheld ORP meter for occasional checks.