19 L Control Bucket for RDWC Systems
Regular price
15,90 €
Regular price
Sale price
15,90 €
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per
This 19 L controller pot is the hub of an RDWC system: the water pump sits submerged inside it, and it is where you measure pH and EC and adjust the solution for all connected pots. Its double-walled black-and-white tank measures 30 cm in diameter and 33 cm in height.
Choose the RDWC 2.0-compatible version, with 32 mm push-fit connections, or the RDWC PRO version, with 50 mm push-fit, depending on your system.
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The summary
- What it is: the only tank in the system that holds no plants and houses the water pump.
- Two versions: 38 mm gasket outlets for a 2.0 circuit, 58 mm for a PRO circuit.
- What sets it apart: six drillings, including a 3/4-inch bulkhead fitting and a side hole for the float valve.
- When to order one: to replace a damaged controller, or to add a second one to a large system.
19 L tank with six drillings, the pumping and dosing hub of an RDWC system
The 19 L controller pot for RDWC systems is the only tank in the network without a plant: it houses the water pump and is used to measure the pH and EC, then to correct the solution for all the connected pots. At 33 cm high and 30 cm in diameter, it has six openings, including a 21 mm side hole for the float valve.
In an RDWC system, one tank carries no plants at all. It houses the water pump, receives your fertilisers and your probe, and acts as the point from which the solution is distributed to all the growing pots. It is the single control point from which you manage the entire installation, regardless of how many pots are connected.
This function is visible on the tank itself. A growing pot has only two holes, those for the connecting tubes, whereas the controller has six, each reserved for a specific fitting. Its capacity, dimensions and black-and-white double-wall construction remain the same as the growing pots, allowing it to sit flush with them on a level surface.
🎛️ Six bores, six functions
Two gasket runs
They receive the connecting pipes: 38 mm on the 2.0 version, 58 mm on the PRO version.
A 26 mm bulkhead fitting
It accepts a threaded 3/4-inch tank fitting, on the front face.
Two holes drilled near the top
They allow inlet and outlet pipes to pass through: 21 mm on the 2.0, 26 mm on the PRO.
A 21 mm side hole
It is reserved for the float valve that maintains the water level.
🔄 The path of the solution
The water pump draws the solution from the bottom of the network through a suction pipe that runs under the fittings, and discharges it into the controller. The solution then returns to the growing pots through the connecting pipes, on the communicating vessels principle, and the loop runs continuously. Because all the water in the network ends up passing through the same point and mixing there, you read a single value for pH and a single one for conductivity, whereas independent pots each drift on their own. It is also at the controller that evaporation is made up, by hand or by the float valve.
Fertilisers should never be poured directly into a growing pot
A dose poured directly at the base of a plant remains concentrated around its roots until the pump distributes it, and it is during this time that root burn can occur. Always pour into the controller, allow the pump to homogenise the circuit, then take a reading half an hour later: the value you get at that point applies to all the tanks.
Top up the level without thinking about it
The 21 mm side hole is intended for the float valve, connected to a canister placed higher than the system. It reopens the water supply when evaporation and plant uptake lower the level, then closes it again once the level is restored. This keeps the pump submerged and the roots in the solution during an absence of a few days, with no mains power or programming needed.
🧢 A lid with a hatch
The controller is closed with a solid 30 cm lid, which is ordered separately in the lid pack. It is made of black polypropylene, faced with white PVC on its upper surface, and it has a small hatch at the edge through which the pump cable passes and, in winter, that of a heater. Closed in this way, your tank is shielded from light, which stops the solution turning green, and it loses less water through evaporation, which limits the concentration of salts between top-ups.
🔩 What you need around it
To do its job, the drilled tank takes the submersible water pump, its solid lid, the seals for its two bulkhead passages and the rigid pipe of the circuit, in 32 or 50 mm depending on the generation. The fittings for the 21 and 26 mm holes are chosen according to what you connect to them. If what you need is to add a growing position rather than a control point, look instead at the grow bed or the pot extension.
Technical specifications
The essentials
- Role
- Pumping, measuring and dosingThe tank does not hold any plants.
- Capacity
- 19 litres
- Dimensions
- 30 cm diameter, 33 cm tall
- Material
- Food-grade polypropylene, double-walledBlack inside, white outside, like growing pots.
The drillings
- Seal grooves
- 2 x 38 mm in 2.0, 58 mm in PRO
- Tank fitting
- 1 hole of 26 mm, 3/4 inch
- Inlet and outlet
- 2 x 21 mm in 2.0, 26 mm in PRO
- Float valve
- 1 side hole of 21 mm
Generation and origin
- Compatibility
- Growrilla RDWC kits of the same generation
- Origin
- Italy, Robassomero
6 further specifications are available in the detailed view.
In the box
- 1 double-walled 19 L control tank, drilled to the diameter of the chosen version.
Volume, dimensions, material, drillings and solution flow path recorded from the component pages and the manufacturer's RDWC 2.0 manual on 07/10/2026.
Manufacturer and product safety
- Manufacturer
- Growrilla di Milone Giulio
- Postal address
- Via Fiano 207, 10070 Robassomero (TO), Italie
- Website
- growrillahydroponics.com
Information provided under Regulation (EU) 2023/988 on general product safety.
Which controller version?
Both tanks are identical in capacity, dimensions and material. This table only compares what determines the connection type.
A tank drilled at the wrong diameter cannot be fixed
The two versions look identical and do not connect to the same circuit. Take thirty seconds to check before placing your order.
| Pot drilling (mm) | Circuit pipework (mm) | Spare push-fit washer | Original kit | Price | Inlet and outlet drillings (mm) | |
|---|---|---|---|---|---|---|
| Recommended Compatible RDWC 2.0Your choice | 38 mm | 32 mm | 32 mm | RDWC 2.0 | 15,90 € | 21 mm |
| Compatible RDWC PROYour choice | 58 mm | 50 mm | 50 mm | RDWC PRO | 17,90 € | 26 mm |
Compatible RDWC 2.0Recommended
How to identify the generation
Pot drilling (mm)38 mm
Circuit pipework (mm)32 mm
Spare push-fit washer32 mm
Original kitRDWC 2.0
Inlet and outlet drillings (mm)21 mm
Compatible RDWC PRO
How to identify the generation
Pot drilling (mm)58 mm
Circuit pipework (mm)50 mm
Spare push-fit washer50 mm
Original kitRDWC PRO
Inlet and outlet drillings (mm)26 mm
Drilling dimensions and pipe diameters noted from the manufacturer's component pages on 07/10/2026.
Help choosing
Which generation of circuit do you have?
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Estimated time
It covers preparing your order and then the transit time quoted by the carrier, counted in working days.
It is not a guaranteed delivery date: public holidays, peak periods, customs or a carrier delay can extend it. The exact amount, in your currency, is worked out in the cart once your address is entered.
A 19 L tank takes up a considerable amount of space for a modest weight: it is shipped in a bulky parcel that cannot be delivered to a letterbox. Orders are dispatched from the workshop in Robassomero, near Turin. The exact shipping costs and final delivery times are displayed in the basket once the delivery address has been entered. Outside the European Union, import duties and taxes remain the responsibility of the recipient.
Frequently asked questions
8 questions
6 key questions, 8 in the detailed view
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