Estimative Index in a bottle

  • Designed to exceed the maximum estimate of plant-growth requirements, the famous nutrient dosing approach pioneered by Tom Barr is now available in a ready-to-use concentrate that removes the guesswork from trying to recreate this powerful and sometimes elusive formula.

    The default dose saturates the water heavily with NPK, Mg, Fe, and Traces, removing nutrient deficiencies from the equation and allows the aquarist to then focus on tuning light, CO2 and other variables. An overview of the EI methodology can be found here.

    Should you use APT Complete, APT Zero or Estimative Index?

    APT / Capstone Series Usage Guide


Expand new possibilities

Above: a fast-growing 'farm tank' using APT Complete. Aquasoil is used as substrate, paired with additional root tabs for faster growth of 'blood vomit' and the red Eriocaulon quinquangulare.

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Unlock the full potential of your planted tank today!

Above: a slower-growing nature-style diorama using APT Complete. 

Capstone Ratio