2Hr Aquarist APT Estimative Index (APT EI) 500ml is a ready-to-use aquarium plant fertiliser concentrate based on the Estimative Index dosing approach pioneered by Tom Barr. It provides a convenient alternative to preparing your own EI fertiliser mix for a planted aquarium.
Designed to support healthy aquatic plant growth, APT EI makes it straightforward to incorporate fertiliser dosing into your regular aquarium maintenance routine.
About APT EI
APT EI brings the Estimative Index approach into a ready-to-use liquid concentrate, removing the need to recreate the formula yourself. The 500ml bottle lets you measure each dose according to your aquarium’s water volume.
How to use
- Dose 5ml per 100L of aquarium water three times per week, or 2ml per 100L daily.
- One capful equals 5ml.
- When using the pump attachment, each pump dispenses 1.5ml.
Choose one dosing schedule, rather than combining both, and follow the product label for full application and maintenance instructions.
Pack size
500ml concentrate.
$159.00 AUD
$46.95 AUD 
