Preventing Failures in Ponds and RAS: Water Monitoring, Biofilter, Aeration, Backup Power and Incident Response

Map your single points of failure

Walk through the system and ask, for each component: if this stops, what happens to the fish or shrimp, and how fast? In ponds the critical items are usually aerators, their power supply and night-time oxygen. In RAS they include the main pumps, blowers, oxygen supply, the biofilter, drum filters and the control system. Write down how long stock can survive each failure at peak biomass; that time defines how fast alarms and backup must work.

Backup power and oxygen

• Size a generator or second supply for the loads that keep animals alive (aeration, oxygen, critical pumps), with automatic transfer where possible.
• Test the generator under load on a schedule and keep fuel records.
• Keep an independent emergency oxygen source (for example bottled or liquid oxygen with diffusers) that works without the main power.
• The aeration sizing calculator and shrimp oxygen-risk calculator help estimate demand.

Monitoring and alarms

Install continuous probes at least for dissolved oxygen, temperature and water level in RAS and intensive ponds, with alarms that reach a person off-site by phone or SMS. Calibrate probes regularly and check readings with a handheld meter. Measure other parameters — pH, ammonia, nitrite, CO₂, salinity — on a schedule set by your species protocol and more often as biomass rises.

Biofilter care in RAS

The biofilter converts toxic ammonia to nitrite and then nitrate. It needs time to mature before full stocking, stable conditions, enough alkalinity and protection from solids. Avoid sudden jumps in feed load, do not clean all media at once, and keep disinfectants or treatments that may harm bacteria away from the loop unless a professional has approved them. Rising ammonia or nitrite is a warning to reduce feeding and investigate.

Pond-specific risks

Ponds can lose oxygen at night after algae blooms crash or during cloudy, hot, still weather. Watch water colour and transparency trends, keep aerators maintained and in reserve, and plan water exchange capacity with your source water quality in mind.

Write and rehearse an incident plan

Step	Action
1. Protect oxygen	Start backup aeration/oxygen; stop feeding
2. Find the cause	Check power, pumps, flows, probes, water quality
3. Call for help	Supervisor, equipment supplier, aquatic health professional
4. Record	Time, readings, actions, mortalities
5. Report if required	Follow national rules for notifiable disease
6. Review	Fix the root cause and update the plan

This guide does not diagnose disease or recommend treatment; for unexplained deaths contact a qualified professional and see the first-response checklist.

Building reliability into a new project

For new or expanded farms, put redundancy into the user requirements: standby pumps and blowers, backup power, alarms, and acceptance tests that prove them. The RAS design guide explains the treatment loop, and the RAS RFQ lets you submit project details for FishMatch review and managed supplier outreach.