Water Treatment & Disinfection
Intake, process and effluent treatment: UV, ozone, denitrification, degassers.
Overview
Water treatment covers everything between raw source water and the fish, plus polishing before discharge — UV, ozone, CO₂ stripping, denitrification, pH control and effluent solids removal.
Where it is used
- RAS grow-out
- Hatcheries
- Marine indoor farms
- Sites with strict discharge rules
Typical applications
- Pathogen control on intake
- CO₂ stripping in closed loops
- Nitrate control for zero-discharge
- Effluent polishing
Benefits
- Biosecurity
- Regulatory compliance
- Consistent water chemistry
Limitations
- Ozone requires trained handling
- UV needs regular lamp replacement
- Denitrification adds complexity and cost
Typical project sizes: Applies to every RAS and most modern hatcheries.
UV vs Ozone vs Chlorination
| Parameter | UV | Ozone | Chlorination |
|---|---|---|---|
| Pathogen kill | Excellent | Excellent + organics oxidation | Good |
| Residual | None | Must be destroyed before tanks | Must be dechlorinated |
| CAPEX | Low–Medium | High | Low |
| OPEX | Lamp replacement | Power + O₂ | Chemicals |
| Best for | RAS, hatcheries | Marine RAS, ballast, effluent | Intake pretreatment |
Buying guide
How to evaluate suppliers
- UV dose validated to third-party standard
- Ozone destruct systems required
- Effluent design must meet local permit
Common purchasing mistakes
- Undersizing UV for peak flow
- Ignoring ozone destruction
- Treating effluent as an afterthought
Technical questions to ask
- What UV dose is guaranteed at end-of-lamp life?
- What ORP setpoint controls the ozone loop?
- What is the effluent guarantee?
Warranty considerations
- 12 months mechanical
- Lamp warranty separate
Maintenance
- Annual lamp replacement
- Quarterly quartz sleeve cleaning
- Monthly probe calibration
Expansion capability
- Reserve manifold capacity
- Modular UV reactors
Energy efficiency
- UV: 1–3 W per m³/h treated
- Ozone: 5–15 kWh per kg O₃
Lifecycle
- 10–15 years reactors, 1 year lamps, 5–7 years probes
Technical specification checklist
Line-by-line items you should include in a vendor-neutral technical specification. Download as CSV to hand to your engineer or drop straight into the RFQ Builder.
Budget guide
| Project size | Indicative CAPEX | Indicative OPEX |
|---|---|---|
| Hatchery water skid | USD 30–100k | USD 0.05–0.15/kg |
| Mid-size RAS | USD 200–800k | USD 0.15–0.30/kg |
| Large RAS + effluent | USD 1–5M | USD 0.20–0.50/kg |
Indicative ranges only. Real budgets depend on site, regulations, redundancy and scope. Use for internal planning — always validate with an engineering study.
Major cost drivers
- Design flow
- Discharge regulations
- Species sensitivity
Optional equipment
- Denitrification reactor
- Effluent solids belt press
- Automatic pH control
Installation notes
- Requires ventilation and safety systems for ozone
Operating cost notes
- UV lamps and probes dominate
Maintenance reserve
- Budget 4–6% CAPEX/year
Procurement checklist
- 1Water analysis of source and target
- 2Discharge permit review
- 3UV/ozone dose specification
- 4Safety plan for ozone
- 5Third-party commissioning test
Supplier evaluation matrix
Score each supplier from 0 to 10 on each factor. Weights are pre-set with defensible defaults — override if your context differs.
| Factor | Weight | |||
|---|---|---|---|---|
Third-party validated dose | 25 | |||
Effluent guarantee | 20 | |||
Safety systems | 15 | |||
Parts availability | 15 | |||
Lifecycle cost | 15 | |||
Lead time | 10 | |||
| Weighted total | 100 | 0.0 | 0.0 | 0.0 |
Decision wizard
Frequently asked questions
Planning a project?
Now that you have the technical picture, get confidential quotations from project-matched international suppliers — or line up equipment financing first.
Continue exploring
RAS – Recirculating Aquaculture Systems
Land-based recirculating systems for salmon, trout, shrimp and other high-value species.
Aeration & Oxygenation Systems
Diffused, surface and pure-oxygen systems for ponds, tanks and RAS.
Filtration Systems
Mechanical and biological filtration for hatcheries, nurseries and grow-out.
Feeding Systems
Automatic, blower, and AI-driven feeders for tanks, ponds and cages.
Short answer
How do you source Water Treatment for a commercial aquaculture project?
Start from the process requirement — biomass, flow, water quality target and site constraints — not from a product catalogue. FishMatch Group converts that requirement into a specification for Water Treatment, sources it from vetted manufacturers and integrators across Europe, Asia and the Americas, and returns like-for-like quotations with lead times, energy consumption and lifetime running cost stated in the same format.
- What we compare:
- Scope, capacity, energy use, lead time and total cost of ownership
- Typical turnaround:
- Depends on scope and site data; no turnaround is guaranteed
- Delivery terms:
- Quotations normalised to EXW / FOB / CIF so prices are like-for-like
- Cost to buyers:
- No fee charged to the buyer
Before you request quotes
Equipment scope
What equipment does a commercial aquaculture project actually need?
A grow-out project typically needs holding infrastructure (tanks, ponds or cages), water movement (pumps, piping, valves), aeration or oxygenation, water treatment appropriate to the system, feeding equipment, grading and handling gear, monitoring and alarms, and backup power. RAS adds mechanical filtration, biofiltration, degassing, disinfection and tighter process control. Hatchery and processing scopes are specified separately.
Which equipment should be specified before requesting quotes?
Specify the items whose sizing changes everything downstream: design biomass and stocking density, water exchange or recirculation rate, oxygen demand at peak temperature, and installed pumping head. With those four fixed, suppliers can quote aeration, filtration, pumps and power on the same basis. FishMatch calculators produce these figures and attach them to the RFQ.
Can equipment be sourced in stages?
Yes, and phased procurement is common. The usual sequence is water supply and holding infrastructure, then aeration and treatment, then automation and monitoring, then processing and cold chain. Staging works when interfaces and capacity headroom are defined at the start; otherwise later phases force replacement rather than addition.