Fertigation Troubleshooting: Dosing, Mixing & Flow
Use this guide to organise the information needed when a fertigation or chemigation system is not delivering as expected. Check the irrigation supply, prepared solution and dosing equipment separately before changing the pump selection.
For I-Feeder equipment, use the model manuals and technical library. Before opening pipework or servicing machinery, isolate the equipment and release pressure according to its instructions. A leak, suspected backflow or failed shutdown interlock requires the system to be made safe before operation resumes.
The pump runs, but the tank level barely changes
Compare measured delivery with the required injection rate. A running motor alone does not establish the volume reaching the irrigation line. Record the pump setting, injection-point pressure, stock liquid and test duration. Check the suction arrangement and any visible blockage or loss of prime using the model manual; do not dismantle pressurised or chemically contaminated components.
University of Georgia Extension recommends calibrating injection equipment at the site. Compare the measured volume over a known time with the intended rate, and recheck during application. Use the manufacturer's procedure for the actual equipment and liquid. Read the UGA chemigation guidance.
The dose changes between irrigation zones
A fixed injection rate gives different dilution when water flow changes. Record each zone's flow, pressure and operating time rather than assuming all zones have the same duty. Discuss flow-proportional control where the process requires a consistent ratio. See dosing automation and fertigation pump selection.
For a batch, the required injection flow is the prepared solution volume divided by the injection time. For example, 300 litres over two hours requires 150 L/h. This arithmetic example is not an application-rate recommendation or a pump capacity claim.
Fertiliser settles, crystals form or emitters clog
Separate undissolved material from a compatibility problem. Review the product, stock concentration, water analysis and temperature. More agitation cannot make incompatible products compatible. NSW agricultural guidance identifies precipitation risks when phosphate fertilisers meet water rich in calcium or magnesium. Confirm preparation and mixing instructions with the fertiliser supplier rather than increasing concentration or combining stocks by trial and error. Read NSW horticultural fertigation guidance.
Send the team photographs and the tank's dimensions, working levels and liquid details. Compare mechanical mixers and agitators with blowers and air agitation against the actual preparation task.
Injection continues after irrigation stops
Stop the application and arrange a competent inspection. The irrigation and injection systems need the appropriate interlocks and backflow protection for the installation. Do not treat a pump's internal valves as proof that the whole water supply is protected.
University of Minnesota Extension explains how irrigation and injection shutdowns can create backflow or tank overflow, and why calibration and protective equipment need checking. Its legal requirements are specific to Minnesota; use the product label and the requirements applicable at your location. Read the Minnesota chemigation safety overview.
Send a useful support request
Equipment model, serial number and photographs of the installation.
Required and measured injection rate, pump setting and operating pressure.
Irrigation zone flow, run time and any changes between zones.
Chemical or fertiliser name, concentration and liquid temperature.
Tank dimensions, working levels, suction layout, power and controls.
What changed before the problem started and when it occurs.
Open I-Feeder Technical & Support or contact the team. For model-specific information, see MXD pump specifications and the knowledge centre.
External references explain general principles and do not constitute an endorsement of I-Feeder. This guide does not replace equipment instructions, chemical labels or site-specific design.