Greenhouse trays and drainage accessories

Conical rubber stopper Ø28–32 mm

The conical rubber stopper has a diameter of 26/32 mm and functions as a plug (like a cork stopper). It is primarily used with commercial tray systems (for example, Ebb & Flow trays) to prevent water from draining until the tray is flushed through the drainage hole. 

Detailed specifications

• Type: conical rubber stopper, functioning like a cork stopper.
• Size: 26/32 mm (in the context of Ø 28–32 mm) — corresponds to the specified range.
• Application: Seals trays during flooding; after it is removed, fresh water can be added and the growing medium and residue flushed through the drainage hole.

Usage recommendations

• When inserted, the stopper completely seals the tray, allowing it to be flooded without leaks.
• Once you remove the stopper, the system automatically allows waste to drain. This makes it easier to clean and prepare the tray for reuse.

Benefits 

The rubber stopper is a practical, inexpensive solution for controlled filling and drainage of trays. It is easy to install and provides a reliable seal during filling, while removing it allows efficient flushing and cleaning without the need for additional mechanisms. This gives you maximum control over the irrigation cycle.

Installation and drainage

Compare the external dimensions with the installation space and check whether a drainage hole is already present. Ebb & Flow systems require compatible inlet and drainage connections, a reservoir, and cycle control.

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The drainage cone for grow trays is a filtering accessory designed to trap dirt and substrate residue as water drains away. It prevents these particles from entering the tray drain.

It is made of durable black plastic and is used as part of the drainage system for plant-growing trays.

HS Valve – single-channel valve 1–2″

HS Valve is a single-channel valve that uses the same channel for both filling and draining the tray. It comes standard with a 3.5 mm internal opening, but the diameter can be modified on request. The valve offers 6 – 31 l/min filling, depending on the diameter and pressure, and 1.7 – 6 l/min drainage. Suitable for installation under filter trays, it is resistant to contaminants and harsh environments. 

Detailed specifications

• Operating function: single-channel - one line serves for both filling and drainage. 
• Hole diameter: standard 3.5 mm, other sizes available on request. 
• Fill flow rate: from 2.3 to 31 l/min, depending on the opening diameter and water pressure. 
• Drain flow rate: from 1.7 to 6.0 l/min, depending on the hole diameter. 
• Hose connection options:
  • ¾″ hose
  • ½″ hose
  • PE hose 8×10.5 mm and 10×12.5 mm
  • PE hose 6×8 mm ([turn0view0])
• Manual bottom valve: allows you to stop filling a specific tray. 
• Installation option: installed under the filters to prevent clogging from leaves and debris. 
• Construction and maintenance: durable design, resistant to demanding growing conditions, with a removable inner cone for easy cleaning. 

Usage recommendations

• Choose a suitable hole diameter (3.5 mm or another size on request), matched to the water pressure for the desired fill and drain flow rate. 
• Install the valve under the tray filter to protect against contamination and ensure trouble-free operation. 
• Use the manual bottom valve when you want to stop filling a specific tray. 
• Easy to clean - simply disassemble the removable cone and remove accumulated particles.

Benefits 

• A unified fill and drain line - fewer components and easier installation.
• Wide flow range - from 2.3 to 31 l/min for filling and from 1.7 to 6.0 l/min for drainage, depending on conditions.
• Flexible connection options for different hoses (½", ¾", PE).
• Easy to install under filters and excellent resistance to clogging.
• Sturdy construction and easy maintenance ensure a long service life.

Installation and drainage

Compare the external dimensions with the installation space and check whether a drain hole is already present. Ebb & Flow requires a compatible inlet, drain, reservoir, and cycle control.

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Quick Valve – dual-channel tray valve

Quick Valve is the fastest and most commonly used valve for EBB & Flow trays from . It has two channels: one fills the tray, and the other drains it. When the water supply stops, the valve automatically drains at ~28 l/min. It is supplied as standard with a 4 mm internal opening (other diameters are available on request). Installation beneath the filters from is recommended to protect against leaves, soil, and debris.

Detailed specifications

• Function: dual-channel (filling + draining); the drainage channel enriches the irrigation water with oxygen during filling for improved root development.
• Filling flow rate: ~9–40 l/min, depending on pressure and the internal opening diameter; standard size is 4 mm, other diameters available on request.
• Automatic drainage: ~28 l/min when the water supply stops.
• Manual lower valve: yes — lets you prevent filling a specific table/tray.
• Connection options:
  • ¾″ hose
  • ½″ hose
  • PE 8×10,5 mm and 10×12,5 mm
  • PE 6×8 mm
• Installation: Ø 27 mm hole in the tabletop for fitting; can be installed beneath sumpplastic filters.
• Durability: designed for long-term use in a “rough” production environment.

Usage recommendations

• Choose the internal opening size (mm) according to the available pressure to achieve the desired filling flow rate.
• Install the valve beneath a filter (sump) to prevent blockage by debris.
• If you need to shut off a particular table, use the manual lower valve.

Summary – Benefits

• Fast filling with an adjustable flow rate based on the opening and pressure.
• Automatic drainage at ~28 l/min when the water supply stops.
• Improves irrigation water quality through oxygenation during filling.
• Flexible options for ½″, ¾″, and PE connections.
• Durable construction for a long service life in greenhouse conditions.

Installation and drainage

Compare the external dimensions with the installation space and check whether a drainage hole is already in place. Ebb & Flow systems require a compatible inlet, drain, reservoir, and cycle controller.

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Staal & Plast Drain Sump Cover

Cover for Sump is a cover designed to close off an existing tray sump when you want to disconnect it from the system. Covering it prevents contaminants from entering and makes it easy to disable the tray sump without removing it.

Detailed specifications

• Product type: sump cover - used when you want to “remove” or deactivate the tray sump.
• Installation instructions:
  1. Clean and dry the area around the sump.
  2. Apply Staal & Plast adhesive around the edge of the cover and let it bond.
  3. Seal the edges to ensure a tight, watertight seal.
• Note: For best results, follow the instructions in the dedicated technical sheet for the adhesive (“glue product sheet”).

Recommendations for use

• Make sure the surface is properly prepared - clean and dry - before gluing.
• Use an original Staal & Plast adhesive product to ensure stability and durability.
• Seal the edges of the cover after installation to prevent dirt and moisture from getting in.

Benefits

The sump cover allows for easy and secure deactivation of the tray sump without dismantling it. It makes it easier to manage the system when a temporary or long-term change is needed, while also preventing contamination thanks to its secure bonding and quality seal.

Installation and drainage

Compare the external dimensions with the installation space and check whether a drain outlet is already in place. Ebb & Flow requires a compatible inlet, drain, reservoir, and cycle control.

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10 mm Siphon Valve – with rubber seal

Siphon Valve is a simple yet effective drain valve with a siphon. It automatically drains a tray to a selected level by adjusting the riser tube. Suitable for automated mobile systems, it can provide continuous drainage if the riser is fully removed. 

Detailed specifications

• Level adjustment: Three preset water retention and drainage levels, adjusted by moving the riser pipe.
• Continuous drainage: If the riser is fully removed, the valve drains the tray completely.
• Full tray: With the riser in its highest position, water is retained in the tray.
• Drainage: Depends on the hole diameter — standard configuration without a reducing ring: a 17.5 mm inner diameter provides a maximum drainage rate of 9 L/min. Other sizes are available on request.
• Rubber gasket: Includes a standard 10 mm rubber gasket, compatible with standard sump filters. An option with a 5 mm gasket is also available. The gasket height affects the operating water level in combination with the riser settings.
• Installation: You can use 1 to 3 Siphon Valves in existing sump filters. The filters allow the lid to be easily removed and the valve installed.
• Design: Very sturdy and resistant to demanding growing conditions. Easy to disassemble for regular cleaning.

Usage recommendations

• Adjust the riser pipe to the desired filling and drainage threshold (3 levels or continuous draining).
• Use the standard 10 mm rubber gasket for optimal operation with standard sump filters. If you prefer a different retention level, look for an option with a 5 mm gasket.
• Install 1–3 valves as needed and as space allows in the filters — they are easy to install and remove.
• Regular cleaning is simple thanks to the sturdy, detachable design.

Benefits

Siphon Valve offers reliable, automatic draining of trays to a preset level using a siphon effect. The standard 10 mm rubber gasket allows easy integration with sump filters, and the design is durable and easy to maintain. The option to use up to three valves in one system provides flexibility and control.

Installation and drainage

Compare the external dimensions with the installation space and check whether there is a pre-drilled drainage hole. Ebb & Flow systems require a compatible inlet, drain, reservoir and cycle controller.

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Greenhouse Trays – Standard Models

Standard greenhouse trays – efficient irrigation and optimal use of space

Trays with a closed bottom are ideal for:

• "Ebb and flow" irrigation systems (Ebb & Flow)
• They offer exceptional flexibility in plant placement
• Close spacing during the initial growth stage and wider spacing in subsequent stages.

Available by request only and can be made in custom sizes and configurations to meet your specific needs.

Available types:

Type 1: Best-selling model

Featuring large lengthwise channels and small crosswise channels, this design ensures even water distribution, a sturdy construction, and exceptional stability. The tray comes with one or two standard valves at the end, and their position can be customized to suit the customer's needs.

Type 2: Special model for small pots

This model has only lengthwise channels for easier cleaning and optimal water distribution. Suitable for small pots, it offers the same option to customize the valves to meet the specific requirements of your system.

Type 3: Model with improved crosswise strength

Designed for automated systems with frameless benches, this model has improved crosswise strength and stability. It allows transport carts to move easily along the benches, without the need for additional aluminum protection.

Custom sizes and requests
The trays are available in a variety of standard sizes, and special sizes and configurations can also be made on request to meet the requirements of your greenhouse.

Benefits

• Efficient irrigation at every growth stage
• Flexibility in plant placement
• Sturdy, durable construction
• Customization options for sizes and configurations

The ideal solution for any greenhouse looking to optimize and sustainably grow its crops!

Installation and drainage

Compare the external dimensions with the installation space and check whether a drainage outlet is already in place. Ebb & Flow systems require compatible inlets, drainage, a reservoir, and cycle control.

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Repair piece for a 175×55 mm sump tray

The Repair Piece for Sump is a solution for repairing damaged sump tray channels. Made to 175 × 55 mm, it allows damaged sections to be easily replaced without having to replace the entire tray. 

Detailed specifications

• Dimensions: 175 × 55 mm — suitable for restoring damaged areas in sump trays.
• Installation: Clean and dry the surface of the damaged area. Apply the branded Staal & Plast adhesive, position the Repair Piece and, if needed, seal the edges to ensure a strong, watertight bond.
• Additional work: After fixing it in place, you may need to drill new holes for valves if the original holes fall within the new section.

Usage recommendations

• Prepare the surfaces thoroughly — they must be clean and dry before gluing.
• Use the original Staal & Plast adhesive to ensure a durable, secure bond.
• After installation, seal the edges if necessary to prevent dirt and moisture from getting in.
• If you need to install valves (sump valves), you can drill new holes in the repaired section.

Benefits

This repair piece for sump trays provides an economical and reliable repair for damaged sections, without the need to replace the entire tray. Its 175×55 mm size allows for precise replacement. The adhesive bond and sealing ensure watertightness and long-term functionality, with the option to install new valves.

Installation and drainage

Compare the external dimensions with the installation space and check whether a drainage hole is already present. For Ebb & Flow, compatible inlet and drain connections, a reservoir, and cycle control are required.

Browse irrigation trays.