Hydroponic systems explained

Hydroponics means growing plants without soil: roots get water, oxygen and dissolved nutrients directly, either in flowing water or in an inert medium such as cocopeat. There is no single "best" system — each one suits different crops, budgets and levels of experience. This guide explains the systems you'll see working at Kryzen's training farm in Pune.

Water-culture systems (NFT)

NFT flatbed

In a Nutrient Film Technique (NFT) system, a thin stream of nutrient solution flows continuously along slightly sloped channels. Plant roots sit in the channel, taking up water and nutrients from the film while staying exposed to air. The solution drains back to a tank and is pumped round again.

Best for: lettuce, other leafy greens and herbs such as basil — fast, light crops harvested in short cycles.

Strengths

• Recirculates water, so consumption is low
• No growing medium to buy or dispose of
• Short crop cycles and easy harvesting at waist height

Watch-outs

• Roots dry out quickly if the pump or power fails — backup is essential
• Solution temperature must be managed in hot weather
• Not suited to heavy, long-season fruiting crops

NFT A-frame (vertical NFT)

The same NFT channels mounted on an A-shaped frame in several tiers. It fits more plants into the same floor area, which makes it popular for small plots and urban farms.

Best for: leafy greens and herbs where space is limited.

Strengths

• More plants per square foot of floor
• Compact — works on terraces and small plots
• Uses the same simple NFT plumbing principle

Watch-outs

• Lower tiers and the shaded side get less light, so growth can be uneven
• More fittings and joints to maintain
• Same pump-failure risk as flatbed NFT

Substrate systems (drip-fed)

Cocopeat growbags

Plants grow in bags of cocopeat (coconut-husk fibre) and receive nutrient solution through drippers several times a day. The cocopeat holds water and air around the roots, giving a buffer if irrigation is briefly interrupted.

Best for: vine and fruiting crops — tomato, cucumber, coloured capsicum — grown inside a polyhouse.

Strengths

• Forgiving: the medium buffers short irrigation gaps
• Suited to tall, long-season, high-value crops
• Bags can be replaced section by section

Watch-outs

• Cocopeat must be washed and buffered before use
• Run-off (drain) water needs to be managed
• Media is replaced periodically

Cocopeat growslabs

Long, flat slabs of cocopeat laid in gutters, each holding a row of plants on drippers. A more uniform, commercial-scale version of the growbag approach, common in high-wire greenhouse production.

Best for: high-wire tomato and cucumber in larger commercial polyhouses.

Strengths

• Uniform root zone across the whole row
• Clean layout that is easy to drain and monitor
• Standard practice in commercial greenhouses

Watch-outs

• Needs a well-levelled floor or gutters
• Higher setup precision than loose growbags
• Same washing/buffering needs as other cocopeat

Dutch buckets

Each plant grows in its own bucket filled with an inert medium. A dripper feeds every bucket and an outlet near the base drains excess solution into a shared return line, which can be recirculated to the tank.

Best for: large fruiting plants — tomato, capsicum, cucumber, gourds — especially for mixed-crop or smaller farms.

Strengths

• Each plant is separate, so problems are easy to isolate
• Can recirculate solution to save water and nutrients
• Flexible spacing and easy to expand

Watch-outs

• Higher cost per plant than slabs or bags
• More individual fittings to check for clogs
• Medium needs cleaning between crops

Polyhouse & protective structures

Most commercial hydroponic systems in India sit inside a protective structure that controls light, heat, rain and pests. The training covers five types:

• Naturally ventilated polyhouse (NVPH) — roof and side vents with insect netting; the most common, lower-cost option for moderate climates.
• Fan & pad polyhouse — exhaust fans pull air through wet cooling pads to lower the temperature; used where summers are hot and dry.
• Polycarbonate house — rigid, long-life panels with better insulation; higher cost, often used for nurseries and research.
• Shade-net house — knitted net that cuts light and heat; low cost, good for leafy greens and nurseries.
• Low polytunnel — small, temporary hoops over beds for season extension and frost or rain protection.

Add-ons such as air-circulation fans, temperature and humidity control, automation and pH/EC IoT monitoring help keep conditions stable and reduce manual work.

How to choose a system

• Start from the market, not the system. Decide what you can sell, to whom and at what price — then pick the system that grows that crop well.
• Leafy greens and herbs → NFT flatbed or A-frame, usually under a shade-net or naturally ventilated polyhouse.
• Tomato, cucumber and capsicum → cocopeat growbags, growslabs or Dutch buckets inside a polyhouse.
• Hot, dry regions → budget for cooling (fan & pad) and solution-temperature control.
• Unreliable power → prefer substrate systems or plan backup power for NFT.
• First farm? → start with one system and one or two crops, and expand once you have stable yields and buyers.

At the training you'll walk through all of these side by side, see the plumbing and dosing up close, and ask which setup fits your land, climate and budget.