The Laboratory for Liquid Life
HydroGrowLabMaster Hydroponics with Free Tools, Guides & Calculators
The definitive free resource for hydroponic growers. Precision calculators, expert plant guides, and data-driven product reviews — everything you need to grow without soil.
Calculators
Hydroponic tools for every grow
Nutrients
Nutrient Mixing Calculator
Calculate exact nutrient amounts for your reservoir based on volume and concentration ratios.
Setup
Reservoir Volume Calculator
Calculate the volume of your reservoir in litres or gallons based on container dimensions.
Nutrients
EC ↔ PPM Converter
Convert between Electrical Conductivity (EC) and PPM across 500, 640, and 700 TDS scales.
Nutrients
pH Adjustment Calculator
Estimate how much pH Up or pH Down solution is needed to reach your target pH.
Lighting
Grow Light Coverage Calculator
Determine the recommended coverage area for your grow light based on wattage and hanging height.
Lighting
Daily Light Integral (DLI) Calculator
Calculate Daily Light Integral from PPFD and your light schedule to optimise photosynthesis.
Plant Guides
Crop targets for pH, EC & harvest
Beginner
Lettuce
Fast, forgiving, and perfect for DWC or NFT. Lettuce is the classic first hydroponic crop — crisp heads in weeks, not months.
5.5–6.5 (aim 5.8–6.2) pH · 0.8–1.2 mS/cm
Beginner
Basil
Aromatic and vigorous under hydroponics. Basil loves steady nutrients and strong light — pinch early for bushier plants.
5.5–6.5 pH · 1.0–1.6 mS/cm
Intermediate
Tomatoes
High-reward fruiting crop that thrives in Dutch buckets and drip systems. Demands stronger light, higher EC, and careful calcium management.
5.5–6.5 pH · 2.0–3.5 mS/cm (stage-dependent)
Intermediate
Strawberries
Compact and highly marketable. Vertical towers and NFT channels keep fruit clean and easy to harvest.
5.5–6.2 pH · 1.0–1.8 mS/cm
Beginner
Spinach
Cool-loving leafy green that bolts fast in heat. Ideal for cooler rooms and winter indoor grows.
5.5–6.6 pH · 1.8–2.3 mS/cm
Intermediate
Peppers
From sweet bells to hot chilies, peppers excel under high light with stable calcium and potassium.
5.5–6.5 pH · 1.8–2.8 mS/cm
Knowledge Base
Growing guides for every system
Beginner
Hydroponics for Beginners
Everything you need to know to start your first hydroponic garden — from choosing a system to your first harvest.
12 min
Beginner
Deep Water Culture (DWC) Guide
The most popular beginner system — affordable, effective, and perfect for leafy greens and herbs.
8 min
Intermediate
Nutrient Film Technique (NFT) Guide
A continuous flow system ideal for commercial and high-density leafy green production.
9 min
Beginner
The Kratky Method Guide
The simplest hydroponic method — no pumps, no electricity, just a container and nutrients.
7 min
Product Reviews
Gear worth measuring twice
4.7 / 5
Best pH Meter for Hydroponics (2026)
Accurate, replaceable probe, and stable in nutrient solution — our pick for serious home labs that check pH daily.
Meters
4.6 / 5
Best TDS / EC Meter for Nutrient Strength
No calibration fuss and tough enough for wet grow rooms — a workhorse for EC/PPM tracking on reservoir day.
Meters
4.4 / 5
Best Beginner Hydroponic Kit
Countertop simplicity with guided lighting — ideal for herbs and lettuce while you learn hydroponic fundamentals.
Systems
4.8 / 5
Best LED Grow Light for Leafy Greens
Efficient full-spectrum coverage for 2×2 to 3×3 leafy green tents without cooking tender lettuce.
Lighting
From the Blog
Fresh notes from the bench
2026-06-12
Why Your Hydroponic Lettuce Tastes Bitter (and How to Fix It)
Heat, high EC, late harvests, and variety choice drive bitterness. Use this lab checklist to sweeten the next tray.
9 min
2026-05-28
500 vs 700 PPM Scale: Stop Comparing Apples to Oranges
Two meters, same water, different PPM — here is how conversion works and why EC should be your source of truth.
8 min
2026-04-18
Lab Bench Essentials: Gear Checklist for Hydroponics
The meters, aeration, and basics that change outcomes — plus a buy-order that prevents wasted money on day one.
9 min
Frequently asked
What is HydroGrowLab?
HydroGrowLab is a free hydroponics resource with precision calculators, plant guides, growing tutorials, and product reviews for soilless growers.
Are the hydroponic calculators free?
Yes. Every tool — PPM to EC converter, nutrient dose calculator, VPD, PPFD, and more — is free to use with no account required.
Is HydroGrowLab free to use?
Yes. Calculators, growing guides, plant guides, and editorial reviews are free with no account required.