"Did I dose macros today?" If you've ever stared at your tank unsure, you already know why a dosing log matters. Plant nutrition only works when it's consistent — and consistency is impossible to judge from memory once life gets busy. Writing down every dose, with the amount and date, turns fertilizing from a vague habit into a measurable routine you can tune.
Open the dosing log →Planted-tank ferts split into two groups. Macros — nitrogen (NO₃), phosphate (PO₄) and potassium (K) — are consumed in larger amounts and drive bulk growth. Micros — iron and the other trace elements — are needed in tiny doses but are just as capable of bottlenecking a tank when missing. Most aquascapers dose them on alternating days so the two don't react in the water column.
| Group | Examples | Typical cadence |
|---|---|---|
| Macros | KNO₃, KH₂PO₄, K₂SO₄, all-in-one macro | 3× / week (EI) or daily light dosing |
| Micros / trace | CSM+B, Fe DTPA, commercial trace | 3× / week, opposite days to macros |
| Liquid carbon | Glutaraldehyde-based products | Daily, if used |
The Estimative Index (EI) deliberately doses nutrients in excess and relies on a large weekly water change (~50%) to reset levels — simple and forgiving for high-light, CO₂-injected tanks. Lean dosing aims to supply just enough, which suits low-tech setups and sensitive shrimp. Neither is "correct"; the right amount depends on your light, CO₂ and plant mass. The only way to find your sweet spot is to log what you dose and check it against your water tests.