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2Hr Aquarist APT e

Artful Intelligence.

Compared to conventional Estimative Index fertilisers:
2X more nitrate limiting for richer colours*
2X more magnesium for stronger growth^

Dose 2ml per 100L daily



200ml lasts ~3mths for a 30 Gal / 115L tank. Pump not included. 


500ml lasts ~3mths for a 65 Gal / 150L tank. Pump not included.


1000ml lasts ~3mths for a 130 Gal / 500L tank. Pump not included.


Our Standard 300ml Pack comes with a calibrated pump. 1ml per press.
Lasts ~3mths for a 40 Gal / 150L tank.


*in terms of the relative amount of nitrogen vs other nutrients per ml.
^in terms of the amount of magnesium per ml.

The EI approach pioneered by Tom Barr is designed to provide a unlimited / unconstrained amount of nutrients to plants based on a professionally Estimated Index of their needs. APTe provides a calibrated version for richer coloration and algae control.
FAQ Here.


APT E / Estimative Index
Liquid inorganic macronutrient fertiliser
NPK (Mg) fertiliser with micronutrients and trace amounts of Boron (B), Copper(Cu), Manganese (Mn), Molybdenum (Mo) and Zinc (Zn).
1.6-1.7-8.5 (+1.6)

1.6% Total Nitrogen (N)
- 1.6% nitric nitrogen
1.7% Total Phosphorus pentoxide (P2O5)
8.5% Total Potassium oxide (K2O)
1.6% Magnesium oxide (MgO)
0.18% Total Iron chelated by EDTA, DTPA and EDDHA.
All nutrients are completely water soluble.

Potassium sulphate (CMC1 CAS n°7778-80-5) Potassium chloride (CMC1 CAS n°7447-40-7) Magnesium nitrate (CMC1 CAS n°10377-60-3) Magnesium sulphate (CMC1 CAS n°7487-88-9) Potassium phosphate (CMC1 CAS n°7778-77-0)

Artful Intelligence

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Questions on usage, dosage or your tank? Let us know.