Qiwei PH-220W pH Meter for Aquaculture and Fish Pond Malaysia
Maintaining a stable pH level is an important part of aquaculture water management. Sudden changes in pH can affect fish health, feeding behaviour, biological filtration and the overall condition of a pond or tank.
The Qiwei PH-220W External Electrode Portable pH Meter provides a convenient way to measure pH and temperature in fishponds, aquaculture tanks and water-treatment systems.
Its external wired electrode can be lowered into the water while the operator holds the main display away from the pond or tank.
The Qiwei PH-220W is available from stock at MTM Precision Malaysia.
Why Is pH Important in Aquaculture?
The pH value indicates whether water is acidic, neutral or alkaline.
Aquaculture water that is outside the suitable range for a particular fish or shrimp species may cause:
Reduced feeding activity
Increased stress
Poor growth
Lower resistance to disease
Ineffective biological filtration
Changes in ammonia toxicity
Unstable water-treatment performance
Higher risk of fish mortality
The correct pH range depends on the species, water source and farming system. Operators should follow the recommended water-quality limits for the specific fish or shrimp being cultivated.
Why Choose the Qiwei PH-220W for Fishpond Testing?
A conventional pH pen requires the complete sensor end of the instrument to be placed directly into the water.
The Qiwei PH-220W uses an external wired electrode, making it easier to test:
Fishponds
Shrimp ponds
Aquaculture tanks
Hatchery tanks
Biofloc systems
Recirculating aquaculture systems
Water-storage tanks
Inlet and outlet water
Filter chambers
The electrode can be positioned in the water while the display remains visible in the operator’s hand.
Key Features
0.01 pH resolution
Measures pH and temperature
External wired pH electrode
Three-point pH calibration
Portable and lightweight design
Suitable for field measurements
Convenient for tanks and ponds
Clear digital display
Available from stock in Malaysia
Main Technical Specifications
Model: Qiwei PH-220W
pH Measuring Range: 0.01 to 14.00 pH
pH Resolution: 0.01 pH
Temperature Range: 0 to 50°C
Temperature Resolution: 0.1°C
Calibration: Three-point pH calibration
Electrode Type: External wired pH electrode
Power Supply: Four 1.5V batteries
Weight: Approximately 88g
Specifications and supplied accessories may vary according to the latest production batch. Please confirm the current configuration with MTM Precision before ordering.
Where Should Aquaculture pH Be Measured?
Testing only one location may not represent the condition of the entire pond.
For better monitoring, measurements may be taken at:
Water inlet
Water outlet
Feeding area
Pond centre
Shallow section
Deeper section
Filtration chamber
Nursery tank
Main culture tank
When comparing readings, use a consistent testing depth and measurement procedure.
When Should Pond pH Be Tested?
Pond pH can change throughout the day due to photosynthesis, respiration, rainfall, feeding, water exchange and chemical treatment.
Aquaculture operators may check pH:
In the morning
In the late afternoon
After heavy rainfall
After changing water
After applying treatment chemicals
When fish show unusual behaviour
When feeding activity decreases
When ammonia or water-quality problems are suspected
Morning and afternoon readings can help operators understand the daily pH variation instead of relying on only one measurement.
How to Use the Qiwei PH-220W in a Fishpond
Inspect the electrode and confirm that it is clean and properly conditioned.
Calibrate the meter using fresh pH buffer solutions.
Rinse the electrode with clean water.
Lower the external electrode into the selected measuring point.
Avoid touching the pond wall, tank wall or bottom sediment.
Move the electrode gently to remove trapped air bubbles.
Wait for the reading to stabilise.
Record the pH value, temperature, location and testing time.
Rinse the electrode after measurement.
Store the electrode using the correct pH-electrode storage solution.
Why Should Testing Time Be Recorded?
A pond may show different pH readings in the morning and afternoon.
Aquatic plants and algae consume carbon dioxide during daylight, which may cause pH to increase. During the night, respiration can increase carbon dioxide and cause pH to decrease.
Recording the time together with the reading helps operators identify whether a change is part of the normal daily cycle or an unusual water-quality problem.
What Can Cause Sudden pH Changes?
Common causes include:
Heavy rainfall
Water-source changes
Excessive algae growth
High stocking density
Uneaten feed
Organic waste accumulation
Chemical treatment
Poor water exchange
Changes in alkalinity
Filter or aeration problems
A pH meter helps identify the change, but the cause should be investigated together with other water-quality parameters.
Should Aquaculture Operators Test Other Parameters?
Yes. pH is only one part of aquaculture water management.
Depending on the farming system, operators may also need to monitor:
Dissolved oxygen
Temperature
Ammonia
Nitrite
Salinity
Conductivity
Total dissolved solids
Turbidity
Alkalinity
For example, ammonia toxicity is affected by pH and temperature. A pH reading should therefore be interpreted together with other relevant measurements.
Why Is the pH Reading Unstable?
An unstable reading may be caused by:
Dry electrode
Dirty electrode
Algae or organic material on the sensor
Old calibration buffer
Insufficient stabilisation time
Air bubbles around the sensing area
Incorrect electrode storage
Ageing or damaged electrode
Rinse and inspect the electrode before recalibrating the meter.
Electrode Care After Pond Testing
Aquaculture water may contain algae, feed residue, microorganisms and suspended material.
After testing:
Rinse the electrode thoroughly
Remove visible contamination carefully
Do not wipe the glass sensor aggressively
Use the correct cleaning procedure for stubborn deposits
Keep the electrode sensing area hydrated
Store it using suitable electrode-storage solution
Recalibrate before important measurements
Correct maintenance can improve response time and extend electrode service life.
Is the Qiwei PH-220W Suitable for Professional Aquaculture?
The PH-220W is suitable for routine field monitoring and operational checks.
For regulatory testing, research or applications requiring documented laboratory accuracy, users should select an appropriate laboratory method, instrument and calibration procedure.
MTM Precision can help customers compare portable pH meters with more advanced water-quality instruments according to their application and budget.
Qiwei PH-220W Available in Malaysia
The Qiwei PH-220W External Electrode Portable pH Meter is available from stock at MTM Precision Malaysia.
It is suitable for fishpond operators, shrimp farms, hatcheries, aquaculture technicians, water-treatment contractors and general water-quality users.
Contact us to confirm the current stock, quotation, supplied accessories and electrode information.
Contact MTM Precision
MTM Precision Sdn. Bhd. (744811-A)
Telephone: +603-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com / enquiry@mtmpre.com.my
Website: www.mtmpre.com.my
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor,
Malaysia.
18 Sep 2026
