2HR APT ESTIMATED INDEX

With 2HR Aquarist APT-EI, Tom Barr's famous pioneering nutrient dosing approach is now available in a ready-to-use concentrate that eliminates the guesswork of trying to recreate this powerful and sometimes elusive formula.

The easiest way to unlock the true potential of your planted aquarium.

APT e / ESTIMATIVE INDEX provides an easy approach to practicing Tom Barr's famous fertilization regimen.

Use it for the quintessential EI experience of unparalleled growth speed through unlimited nutrition - but be sure to be equally disciplined in growing and maintaining the plants.