Hydroponicity
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Hydroponicity

A precision nutrient calculator for side-hustle growers. Research-grade math, an operator-friendly surface.

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  • EC ↔ ppm converter
  • Fertilizer label decoder
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Fertilizer label decoder (oxide → elemental)

A guaranteed-analysis label reports P and K as oxides (P₂O₅, K₂O). Every ppm calculation needs the elemental fraction. Enter the label numbers to decode them — do this first, before any dosing math.

Guaranteed analysis (label %)

Elemental composition

What the ppm engine actually uses

Nitrogen (N)4.00%
Phosphorus (P)7.86%
Potassium (K)31.54%
Calcium (Ca)0.00%
Magnesium (Mg)0.00%
Sulfur (S)0.00%

ppm preview

Concentration if you dissolve this product [II-3.1]

N
40.0ppm
P
78.6ppm
K
315.4ppm

Store %element for the actual product form you buy (the hydrated salt), not the anhydrous salt. Epsom salt is MgSO₄·7H₂O at 9.9% Mg — the anhydrous figure (20.2%) would halve your weigh-out. When the label and a table disagree, trust the label.

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