Hydroponic Reservoir Size Guide: How to Size Your Tank
Home > Hydroponics > Hydroponic Reservoir Size Guide: How to Size Your Tank Last Reviewed: August 2026 | Author: Faisal Habib, CEA Systems Specialist | Fact-Checked: Horticultural & System Accuracy Verified | Expert Reviewer: Wara Danish, MSc Plant Biology Difficulty: Intermediate | Setup Time: 2 Hours | Estimated Cost: $150 to $500+ ⚡ Quick Answer: Sizing a Hydroponic Reservoir Determining your hydroponic reservoir size uses the formula $V_{\text{total}} = [(N_{\text{plants}} \times V_{\text{plant}}) + V_{\text{system\_flood}}] \times 1.25\text{ buffer}$. Maintain a minimum of 2.5 to 5.0 gallons per plant depending on crop type. Leafy greens need 0.5–1.0 gallon each; fruiting tomatoes need 3.5–5.0 gallons each. A properly sized reservoir prevents EC spikes…