APT E/Estimative Index Fertilizer - 2Hr Aquarist
- 300ml Pump Bottle
- 500ml Refill
- 1000ml Refill
With the 2HR Aquarist APT-EI, 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.
An overview of the EI methodology can be found here.
Dose 5ml per 100L 3 times per week or 2ml per 100L daily.
FAQ here.
300ml. Lasts ~3mths for a 40 Gal / 150L tank.

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Product Information
Shipping & Returns
Shipping & Returns





APT E/Estimative Index Fertilizer - 2Hr Aquarist
APT E/Estimative Index Fertilizer - 2Hr Aquarist
- 300ml Pump Bottle
- 500ml Refill
- 1000ml Refill
With the 2HR Aquarist APT-EI, 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.
An overview of the EI methodology can be found here.
Dose 5ml per 100L 3 times per week or 2ml per 100L daily.
FAQ here.
300ml. Lasts ~3mths for a 40 Gal / 150L tank.

Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
- 300ml Pump Bottle
- 500ml Refill
- 1000ml Refill
With the 2HR Aquarist APT-EI, 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.
An overview of the EI methodology can be found here.
Dose 5ml per 100L 3 times per week or 2ml per 100L daily.
FAQ here.
300ml. Lasts ~3mths for a 40 Gal / 150L tank.









