MasterLine I

MasterLine I

  • Micronutrient fertiliser
  • Contains iron, manganese, cinc, boron, copper and molybdenum
  • Daily or weekly dosing
  • Recommended use with MasterLine II and MasterLine Carbo
  • Available in 500 ml and 1000 ml
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MasterLine I is a concentrated micronutrient combination fertiliser for aquatic plants. It contains strongly chelated iron, manganese, zinc, boron, copper and molybdenum. It is recommended to use MasterLine I together with MasterLine II and MasterLine Carbo. In this way the aquatic plants have all the nutrients necessary for healthy growth. Thanks to the high-quality chelators, the nutrients in MasterLine I retain their properties over a longer period of time, keeping the water crystal clear and offering the possibility of a weekly dosage. This gives the aquarist the freedom to choose between the two dosages.


  • Available in 500 ml, 1.000 ml and 5.000 ml unit sizes
  • Contains iron, manganese, zinc, boron, copper, and molybdenum
  • The full micronutrient supply
  • Daily or weekly dosage


Daily dosage
Lots of light (>0.5 Watt per litre) + CO2 1 ml per 30 litres*
Little light (<0.5 Watt per litre) + CO2 1 ml per 50 litres*
Weekly dosage
Lots of light (>0.5 Watt per litre) + CO2 7 ml per 30 litres*
Little light (<0.5 Watt per litre) + CO2 7 ml per 50 litres*

(*1 ml per 30 litres = 0.09 mg/l Fe)

The recommended dosage is only a guideline. Depending on the aquarium, the dosage of the fertiliser can be reduced or increased to achieve optimum results.


Use in combination with activated carbon or UV lamps is not recommended, as the use of these substrates or tech can alter the nutrient properties. Shake bottle well before use. Store in a cool place without direct sunlight.



MasterLine was founded in 2016 out of passion for aquaristics, which has since become the brand's slogan. Masterline fertilisers contain a balanced mix of nutrients that are essential for the healthy growth of aquatic plants. The Masterline fertiliser system is designed to be particularly effortless to use and takes the user by the hand with a very simple concept. The specially calculated compositions provide the aquatic plants with all the necessary macro and micro nutrients and ensure good growth and vibrant colours.

General information

Item no.
EAN 9355478926125
Weight 1,20 kg
Shipping weight 1,60 kg

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Dariusz A.
Holy shit!!!
6th June 2022
MasterLine - I - 5.000 ml
MasterLine - I - 5.000 ml

Changed from ADA to MasterLine fertilizers just to try something different and cheaper and boy I got surprised. (read more)