Estimative Index Dosing Calculator
Calculate precise fertilizer doses for your planted tank. Supports Standard EI, Lean EI, and PPS-Pro methods with printable weekly schedules.
Understanding EI Dosing
Estimative Index (EI) was developed by Tom Barr as a simple, no-test approach to planted tank fertilization. The principle is straightforward: dose excess nutrients so plants never lack anything, then reset with a large water change.
Unlike methods that try to maintain precise nutrient levels, EI accepts that we cannot perfectly measure or control every variable. By providing more than plants need, we eliminate nutrient deficiency as a cause of poor growth or algae.
Key points: Use RO/DI water remineralized to your target GH/KH, or dose extra K2SO4 if using hard tap water. Store dry fertilizers in a cool, dry place. Mix solutions fresh if using liquid dosing.
Fertilizer Reference
| Fertilizer | Chemical Name | Provides | Density |
|---|---|---|---|
| KNO3 | Potassium Nitrate | K, NO3 | ~6g/tsp |
| KH2PO4 | Monopotassium Phosphate | K, PO4 | ~6g/tsp |
| K2SO4 | Potassium Sulfate | K, SO4 | ~6g/tsp |
| CSM+B | Chelated Trace Mix + Boron | Fe, Mn, Zn, Cu, B, Mo | ~4g/tsp |
| Fe DTPA/EDTA | Chelated Iron | Fe | ~5g/tsp |
Teaspoon measurements are approximate. For precision, use a digital scale that measures to 0.01g.
Track your planted tank parameters and dosing schedule with MyAquaLog.
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