RDWC PRO hydroponic kit, 3 to 24 buckets

This is why a RDWC is managed differently from a row of independent pots. You are not adjusting twelve separate crops, you are adjusting a single crop spread across twelve positions. The trade-off is that a dosing error propagates everywhere within minutes, which is why your electronic pH meter deserves a place next to the controller rather than at the back of a drawer. Always measure before correcting, then measure again half an hour later: in between, the pump will have redistributed your correction throughout the entire system. This shared environment also requires that all your plants are at the same stage, a plant in flower and a young cutting sharing the same circuit will both compromise on a solution that suits neither. Solution temperature should be monitored at the same point; the practical upper limit is around 24 °C, beyond which dissolved oxygen becomes scarce precisely when submerged roots need it most.

A 19 L pot filled with flowing water looks very much like a deep water culture grow bed in aquaponics, and the temptation to connect the network to a pond is understandable. Two things change when you do. You lose the freedom to make corrections, because the pH range that suits plants is not the same as the one that suits fish and nitrifying bacteria, and that is the dividing line between the two growing methods. What you gain, on the other hand, is a considerable buffer volume, which absorbs fluctuations far better than a channel.

The second issue is mechanical. Water from a fish tank carries suspended solids that an inline filter is not designed to handle continuously: mechanical filtration upstream becomes the missing piece. The nitrogen cycle takes place before the pot network in any case, within the tank and the biological filter. In practice, a setup of this kind therefore requires a settling chamber and a biological filter sized for the fish load, with the RDWC network coming only afterwards, at the end of the chain.

The nine configurations differ in floor footprint as much as in plant count. The 12-pot format is the only one available in two layouts, three rows or four rows: the first runs along a wall, the second clusters into a square. Measure the room before deciding, as both hold the same number of plants. The 16-, 18- and 24-pot formats require a dedicated room and access to water, otherwise manual top-ups become a daily chore. In all cases, allow a passageway of at least 60 cm on one side, so you can reach the controller and rinse the filter without moving a full pot. The number of pots should ultimately be chosen according to what you plan to grow: 24 positions fill up quickly with lettuces or herbs, whereas a 3- to 6-pot format is better suited to full-sized plants that each need their own canopy space and support.

You receive the growing pots, the controller pot with its lid and valve, the inline filter, the two pumps, one air stone per pot, and the 50 mm pipework with its elbows, seals and pre-drilled lids. Nothing is glued or screwed: the push-fit fittings clip together by hand, and you can assemble or disassemble an entire network without reaching for a single tool. This is what allows you to change your configuration between cycles, drain the circuit, add or remove a pot, then refill straight away, without cutting or resealing anything. The components are manufactured in Italy, and the pots feature the same double-wall construction as the rest of the range: black on the inside and white on the outside. The black blocks light and prevents algae from establishing themselves; the white reflects lamp energy and limits solution heating in an enclosed space.

Three families of parts need replacing over time. The 50 mm push-fit seals lose their elasticity after repeated assembly and disassembly and eventually start to weep. The cylindrical air stones become clogged with mineral deposits and can be identified by the large, irregular bubbles they produce. The 14 cm net pots crack when a mature plant is pulled out with force.

A cracked pot can't be repaired either: polypropylene doesn't bond cleanly, and it's the 19 L grow bed that needs to be ordered as a standalone item. The rest of the system, however, can be dismantled and reassembled without tools, which means a PRO can be reconfigured between two cycles rather than replaced.

Allow approximately 19 kg per pot once filled, to which you add the wet grow medium and the plant, bringing a 24-pot system well beyond 500 kg spread across a few square metres. The floor should therefore be assessed before the first fill: a concrete slab, a load-bearing floor or a tiled surface is suitable; old timber floorboards or a top resting on trestles far less so. Every pot must also sit at exactly the same level, to the millimetre, as gravity alone equalises the water height between them: a pot sitting fractionally high receives less water than its neighbours, and you will notice it in the plants long before you see it in the water level. Running a spirit level under each pot during assembly saves a great deal of troubleshooting weeks down the line.