01 · AquaGrow
What it is
Ammonia and nitrite are waste-related substances that need monitoring. Their risk cannot be judged from water colour or smell. Ammonia interpretation also depends on pH, temperature and the test’s reporting units.
Signs to watch for
- Feeding or activity falls without an obvious single cause.
- Waste accumulates or water-quality trends worsen.
- Ammonia or nitrite tests rise above the hatchery’s stage-specific action limits.
Common causes
- Feed, animal waste or dead live feed adds more load than the system can handle.
- Water treatment, circulation or a biological filter is not working as planned.
- Stocking or feeding exceeds the system’s capacity.
How to confirm the cause
- Use suitable tests and record whether ammonia is total ammonia nitrogen (TAN) or un-ionised ammonia; do not compare unlike units.
- Check pH, temperature, DO, source water and filter operation with the technician.
What to do immediately
- 1
Ask the technician to interpret the results and assess animal condition urgently.
- 2
Maintain safe aeration and stop unplanned inputs. Adjust feed according to stage and consumption, not a blanket starvation rule.
- 3
Inspect waste removal and water treatment. Use only tested, suitable replacement water under a controlled plan.
- 4
Retest and record the response. Do not add several ammonia-removal products or probiotics as a quick experiment.
Prevention: your practical checklist
- Track water tests alongside stage, stocking and feed records.
- Maintain treatment systems and remove waste with a suitable larval-safe method.
- Test source water and plan capacity before increasing stocking.
When to call an expert
- Seek immediate help if abnormal tests accompany deaths or severe weakness.
- Get technical review if readings keep rising or the test units are unclear.
Farmer questions
Is TAN the same as toxic ammonia?
No. TAN includes different ammonia forms. The un-ionised fraction depends on water chemistry. Ask the technician to interpret the test with pH, temperature, salinity and units.
Is clear water safe?
Appearance cannot confirm ammonia or nitrite levels. Use an appropriate test and the hatchery’s stage-specific action plan.
Can a product replace waste management?
Do not assume so. Establish the source of the load and check system capacity. Choose any input only after testing and qualified advice.
Sources & further reading
AI-assisted educational content and translations, source-checked 17 October 2026. Not an individual diagnosis or prescription. Independent aquaculture-health and native-language specialist approvals have not been supplied. Sources do not endorse AquaGrow.
- SHAPHARI hatchery operating guidelines — production, biosecurity and records ↗MPEDA; linked guideline, not AquaGrow certification or a legal-compliance audit
- Hatchery operations and assessment framework (2007) ↗FAO FTP 446; historical P. monodon manual, not a vannamei treatment protocol