Commissioning a RAS facility isn’t just “start the pumps and see what happens.” It’s the controlled, documented process of proving that a tightly coupled set of mechanical, electrical, automation, and biological systems will keep living stock safe—at scale—day after day.
And that’s what makes RAS commissioning unique: you’re not commissioning a building or a process skid in isolation. You’re commissioning a life-support ecosystem.
Why RAS commissioning is different
A modern RAS site can include miles of piping, distributed pumps and valves, multiple treatment trains, and a control system coordinating everything in real time—while the end “customer” is a live organism. Pure Salmon Technology (PST), which commissions high-tech RAS facilities across Norway and Japan (and plans to expand further), describes the work as fundamentally multidisciplinary and lifecycle-wide.
Water quality targets aren’t “nice to have.” They’re mission-critical: dissolved oxygen, CO₂ stripping, ammonia conversion, disinfection, and solids management all have to perform together and stay stable.
The RAS process stack you’re proving (and documenting)
While every facility has its own “recipe,” most RAS loops include a familiar sequence of treatment steps: solids removal, ammonia removal (biofiltration), CO₂ removal/degassing, oxygenation, and disinfection (often UV and sometimes ozone), with makeup water treated before entering the loop.
That means commissioning isn’t one event—it’s a phased ramp from inert assets to a stable biological process.
A practical commissioning roadmap for RAS facilities
1) Start commissioning earlier than you think
PST puts it bluntly: commissioning needs to be “inserted into the project lifecycle at an early stage,” so requirements are shared and traceable across tools, people, and processes.
In RAS, late discovery is expensive: a missed sensor range, swapped valve orientation, or poor CIP access can surface only when the system is wet—and then everything slows down.
2) Dry commissioning: prove controls before water
Before you introduce water to full systems, you want confidence in:
- I/O checkout, loop checks, alarms, and interlocks
- Sequence logic (fail-safe positions, shutdowns, permissives)
- Redundancy behavior (pump duty/standby changeover, UPS/backup power logic)
This is the cheapest time to find automation issues.
3) Wet commissioning: leak-tight, clean, and hydraulically correct
Once you go wet, you’re validating:
- Mechanical integrity (leaks, vibration, alignment, cavitation risk)
- Flow/pressure performance vs. design intent
- Filter backwash behavior and waste routing
- Tank levels, overflows, and emergency drain paths
4) Biological start-up: schedule it like a critical path item
The biofilter is often the pacing item for “first fish.” A ZHAW biofilter start-up guide recommends planning 6–8 weeks for a biofilter to be ready before stocking, to reduce risk of ammonia/nitrite poisoning while nitrifying bacteria establish.
That timeline has major implications for turnover planning, staffing, and when you can realistically start gradual stocking.
5) Biosecurity and disinfection: verify effectiveness and safety
High stocking density increases disease risk, which is why UV and ozone are common tools in RAS water treatment.
But ozonation also introduces hazards and control nuances—ozone demand varies with organics, and poor materials selection can create long-term reliability issues.
Commissioning should prove not just that disinfection systems run, but that they’re controlled safely, monitored appropriately, and integrated into operating procedures.
(Xylem) (Oxidation Technologies)
6) Operational readiness and performance verification
This is where you tie everything together:
- SOPs, training, spares, calibration plans
- Alarming philosophy (who responds, how fast, what’s the escalation path)
- Documented performance tests and acceptance criteria
- A clean handover package that an operations team can actually use
What “good” looks like: lessons from the Pure Salmon Technology case study
PST’s SalMar Tjuin requires 25.3 tons of fish feed per day and produces ~20 million smolts per year—a scale that makes informal, spreadsheet-based commissioning difficult to sustain.
In the case study, PST highlights several commissioning pain points that will feel familiar in RAS projects:
- Coordinating subcontractors across distance and time zones: they describe scenarios where leads were hundreds to a thousand kilometers away and previously relied on calls, email, and travel to validate readiness.
- Preventing “issue pile-ups” at the end: PST wanted issues found during installation to be tracked and resolved through earlier stages, rather than surfacing all at once during final commissioning.
- Traceability down to equipment level: PST emphasized tagging each piece of equipment with a unique code to maintain an audit trail and proof of proper installation.
- Repeatability across a portfolio: PST notes using the same commissioning approach across projects in multiple geographies (including Japan, the U.S., and Brunei) and across phases from mechanical and electrical installation through end-of-commissioning.
They also reference aligning commissioning management with CIBSE Commissioning Code M, which frames commissioning management as ensuring commissioning is correctly executed and reflects modern best practices.
A field-ready RAS commissioning checklist (steal this)
Use this as a practical “don’t-forget” list:
- Define measurable acceptance criteria for each subsystem (flows, pressures, UV dose logic, oxygenation capacity, CO₂ stripping, etc.).
- Confirm device tagging strategy matches turnover/audit needs (equipment-level traceability).
- Complete I/O checkout + loop checks before wet tests (reduce rework).
- Validate alarm setpoints and escalation paths (ops-ready, not just “installed”).
- Pressure/leak test and document results system-by-system before full integration.
- Verify backwash/waste handling doesn’t compromise hydraulics or overflow safety.
- Calibrate critical probes (DO, pH, ORP if used, conductivity, turbidity where applicable).
- Validate UV/ozone safety interlocks and materials compatibility (where ozone is used).
- Plan biofilter maturation explicitly in the schedule (often 6–8 weeks).
- Run a staged wet-commissioning ramp: “small loop → train → full facility,” documenting each gate.
- Issue management: track, prioritize, and close issues continuously—don’t let them bunch up at the end.
- Produce weekly/monthly reporting that stakeholders can understand (progress, risks, readiness gates).
The takeaway
RAS commissioning succeeds when it’s treated as a program—not a final phase—combining disciplined testing, tight documentation, and biological reality (especially biofilter maturation) into one coordinated delivery.
