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

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

#500ml

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

#1000ml

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

#standard

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

Why

*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.

Ingredients

GUARANTEED ANALYSIS
Total Nitrogen (N)........................................... 2.0%
2.0% Nitrate Nitrogen
Available Phosphoric Acid (P2O5)....................1.37%
Soluble Potash (K2O)....................................... 8.0%
Magnesium (Mg)............................................. 1.60%
Iron (Fe) ...........................................................0.16%
0.16% Chelated Iron
Derived from: Potassium Sulphate, PotassiumPhosphate, Potassium Chloride, MagnesiumNitrate, Magnesium Sulphate, DTPA Iron, EDTA Iron, EDDHA Iron

Further information here.