Flexi-N Compatibility

Storage and tank volumes


Some fertiliser products are not compatible. Caution is therefore required when storing liquid fertiliser in tanks that contain, or have contained a different liquid fertiliser product. Mixing products can negatively affect a product’s usability and when mixing acidic liquids or chlorine based compounds with Flexi-N can generate dangerous reactions.

The table below shows the compatibility of different CSBP liquid fertilisers when placed in a storage tank. A tank must contain less than 10% (e.g. 4,300 litres or 4 cubic metres for 43,000 litre tanks) of the previous CSBP liquid fertiliser stored.

Storage tanks and volumes

Below are some common storage tanks and their capacity by volume and weight.  
Note: Flexi-N tanks don’t empty completely, always allow for 2-3 tonnes leftover product when refilling.

Flexi-N tank sizes table

What are the benefits of Flexi-N tank telemetry? Find out here.



The physical characteristics and low water content of liquid fertilisers make them unideal for mixing with some agricultural chemicals, due to the density and viscosity of liquid fertilisers making them difficult to pump and agitate. The addition of water will assist with the mixing of crop protection chemicals.


The single most important machinery factor is boomsprayer agitation. Without adequate tank agitation, some chemical formulations will layer and/or separate from liquid fertilisers.

Formulations and mixing orders for chemicals

The mixing order for chemicals being added to liquid fertiliser should follow the same mixing order as recommended for addition to water. The least soluble chemical should be added first with the most soluble in last, followed by wetting agents and oils as required.

CSBP recommends that all chemical and fertiliser mixes are always jar-tested before use.

Mixing order.

When tank mixing pesticides with CSBP liquid fertilisers ensure 20% water is added to the mix.

Add products in the following order:

  1. Water - ~70% of water volume
  2. Water conditioners or buffers
  3. Wettable powders (WP)
  4. Water dispersible granules (WG)
  5. Flowable or suspension concentrates (SC)
  6. Emulsifiable concentrates (EC)
  7. Soluble liquids (SL)
  8. Adjuvants
  9. Water – dilute to volume

Jar test protocol

When conducting jar tests ensure the mixing volumes are relevant to your intended field application. The quantities used in the jar test can be extrapolated directly from the field rates used. For example, if using: Flexi-N 50L/ha, water 10L/ha and fungicide 2L/ha, then conduct a jar test with those exact same ratios: 50mL:10mL:2mL or 500mL:100mL:20mL.

As it’s a field test, it’s acknowledged that the amounts are going to be close but never exact.


Important considerations when mixing chemicals

  • CSBP recommends that all chemical and liquid fertiliser mixes are jar tested before use
  • When tank mixing with CSBP liquid fertilisers always add 20% water to the mix
  • Granular formulations are designed to disperse in water. Always pre-mix granules in water prior to adding liquid fertiliser
  • Pesticide efficacy is not compromised by using liquid fertilisers as a carrier provided due consideration is given to dilution, the necessary adjuvants and coverage of the target species (particularly important for grass weeds)
  • Some suspension concentrates are not physically compatible with NS-Rapid and Liqui-NS. These formulation types should always be jar tested and require pre-mixing in 20% water prior to the addition of liquid fertilisers
  • EC formulations may layer without sufficient agitation of tank contents. Tank agitation needs to be continuous from the time of mixing in order to form a stable mix (recommended agitation capacity is 300 l/minute)
  • Concentrated glyphosate formulations (e.g. Roundup PowerMAX™) may mix more readily when pre-mixed in water before adding to liquid fertiliser, with thorough agitation required
  • Always use the recommended rates of surfactants when using liquid fertiliser and chemical mixes

Warning: 2, 4-D amine (IPA salt) is not physically compatible with Flexi-N, Flexi-NK and NS-Rapid.

Speak to your area manager to maximise returns on your nitrogen spend today.

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