Hydroponic gutter kit with pump, 10 to 80 plants

The first two sizes are built on one-metre channels: two for the 10-plant, four for the 20-plant, fed by the same 16 W Syncra 1.0 pump. Beyond that, the number of channels stays fixed at four and it is their length that increases, from 2 m for the 40-plant to 3 m for the 60-plant and 4 m for the 80-plant, with each channel taking 5 baskets per metre. The pump follows the length to be served: a 23 W Syncra 1.5 on the 40-plant, a 32 W Syncra 2.0 on the 60-plant and a 45 W Syncra 3.0 on the 80-plant. The choice is therefore made first on the length your support can accommodate, since the width remains that of four channels on all the larger sizes.

The volume of the profile is what makes these gutters special: they take lettuces, herbs and strawberry plants just as well as large-growing plants such as tomatoes or cucumbers, whose roots quickly saturate a flat gutter. The 8 cm baskets are filled with clay pebbles, an inert grow medium that holds the root ball without retaining excess water, and each basket takes one plant that already has roots. Climbing plants need staking that is independent of the gutters, which you attach to your structure or to a wire stretched overhead. The guide to what to plant in hydroponics, season by season helps you plan successive crops that follow one another without leaving an empty space.

Nutrient film systems, such as the NFT hydroponic system, 36 plants, 80 mm channels, meet a different need from this kit. In their 100 x 80 mm channels, sloped at roughly 1 cm per metre, a film of solution a few millimetres deep runs beneath 5 cm pots, which suits lettuces grown to full size, herbs and strawberries; the system arrives complete, with its frame and a 64 L reservoir. The channels in this kit, laid level, instead hold a few centimetres of solution stirred by the jets, in an 18 x 14.7 cm profile fitted with 8 cm baskets, so the bulky roots of tomatoes and cucumbers find their reserve there. The NFT system is therefore for you if you are starting from scratch with leaf and strawberry crops, and this kit if you already have a reservoir and a support, or if you are aiming at large plants in channels of 1 to 4 m.

In an aquaponic setup, these gutters can receive water from a fish tank, since their principle is that of a circulating-solution culture. However, rearing water carries suspended waste and uneaten feed, which eventually clog the calibrated jets of the manifold and settle at the bottom of the gutters. Gutter growing should therefore be run behind a mechanical filter, with the pump drawing from a compartment where the water has already settled rather than from the fish tank itself. The nutrients then come from the fish and from bacterial nitrification, which means you need to monitor the pH and the look of the foliage instead of dosing a complete fertiliser; our guide to deficiencies in aquaponics lists the signs to watch for.

The pump connects to the manifold by a fitting specific to each size, then a 20 mm barbed tee distributes the solution between the channels through black 18 x 22 mm tubes, with elbows and manifold tees secured by clamps. Because this manifold is supplied as separate parts, the spacing of the channels is up to you, and you adapt the distribution to the width of your support rather than the other way round. The ends of the channels are laser-welded and fitted with threaded outlets with a 3/4 inch thread, closed by tapped caps and flat seals. If your support is made of 30 mm square tube, the tees and caps for 30 x 30 square tube are the ones used on the original frame.

The pump is the only electrical device in the kit, and its consumption is low compared with grow lighting. On the 10 and 20 plant models, its 16 W comes to about 0.38 kWh per day when running continuously, while the Syncra 3.0 on the 80 plant model uses about 1.08 kWh per day for four 4 m channels. Continuous running is the rule during the day; at night, you can switch the pump off to save electricity, except in hot weather, when circulation keeps the solution oxygenated. A simple timer is enough for this setting, and the daily timer fits between the socket and the pump. If you line up several kits, each keeps its own pump, and the total consumption remains the sum of these few tens of watts, well below that of a single horticultural lighting bar.

The parcel contains the double-wall gutters and their drilled lids, one level tube per gutter, the access plugs, the 8 cm slotted baskets, the Syncra pump matching the format and the whole distribution manifold, fittings, clamps, threaded plugs and seals included. The gutters are made in France, from a white double-wall plastic that reflects light and keeps the roots in the dark. The larger formats call for a little organisation on delivery, since the 80-plant version weighs 48.5 kg and includes 4 m gutters that two people will need to handle. Before ordering a large format, measure the free length of your greenhouse or workspace, because the 3 m and 4 m gutters need that much clear length, plus access to the manifold and room for the reservoir beneath their level tubes.