Zebrafish Water Quality Fundamentals
Water quality is the single most important factor in zebrafish husbandry. Zebrafish (Danio rerio) are freshwater fish native to South Asian streams and require specific water chemistry for optimal health, breeding, and experimental reproducibility.
Key parameters and their biological significance:
- Temperature directly controls metabolic rate, immune function, and developmental timing
- pH affects gill function, ammonia toxicity (higher pH = more toxic NH₃), and drug pharmacokinetics
- Conductivity reflects total dissolved solids; too low causes osmoregulatory stress, too high inhibits breeding
- Nitrogen cycle (ammonia → nitrite → nitrate) is managed by biological filtration; failure causes acute toxicity
- Dissolved oxygen must exceed 6 mg/L; aeration and flow rate are primary controls
Modern recirculating aquaculture systems (RAS) automate much of the water treatment, but manual monitoring remains essential for detecting equipment failures, biofilter upsets, and gradual parameter drift.