Unlike soil growing, hydroponic plants get 100% of their nutrition from the solution you mix, which makes getting the nutrient concentration and cost right critical for both plant health and budgeting. This calculator estimates your nutrient solution cost based on reservoir volume, target EC (electrical conductivity), and the number of plants you're feeding.
Nutrient Solution Needed ≈ Reservoir Volume × Number of Refill Cycles, with fertilizer dosage calculated from your target EC and the crop's growth stage. Total Nutrient Cost = Fertilizer Quantity (kg) × Price per kg, scaled across your full growing cycle.
| Growth Stage | Target EC (mS/cm) |
|---|---|
| Seedling | 0.8-1.2 |
| Vegetative growth | 1.6-2.2 |
| Flowering/fruiting | 2.0-2.8 |
| Leafy greens (lettuce, herbs) | 1.2-1.8 throughout |
For an NFT system with a 200-liter reservoir growing lettuce at EC 1.5, refreshed weekly over an 8-week cycle: total solution volume across the cycle is roughly 200 × 8 = 1,600 liters. At typical hydroponic fertilizer dosing (≈1.2 g/liter for EC 1.5), that's about 1.9 kg of fertilizer for the cycle — at PKR 450/kg, a nutrient cost of roughly PKR 855 for a full lettuce crop, which is a small fraction of most hydroponic operating budgets compared to electricity and labor.
Leafy greens like lettuce and herbs prefer a lower EC of 1.2-1.8 mS/cm throughout growth, while fruiting crops like tomatoes and cucumbers need higher EC (2.0-2.8) especially during flowering and fruit set, when nutrient demand peaks.
In recirculating systems (NFT, DWC), most growers fully replace the solution every 1-2 weeks and top up water daily in between, since plants absorb water faster than nutrients, which gradually shifts the EC balance if not corrected.
Yes — deep water culture (DWC) and NFT systems typically use less total nutrient solution per plant than media-based flood-and-drain systems, since there's no absorbent growing medium holding excess solution that eventually needs replacing.
Not reliably — hydroponic nutrients are formulated to be fully water-soluble and balanced for soilless growing, including micronutrients that soil normally provides. Standard granular fertilizers often don't dissolve completely and can clog drip systems.