Design a Growing Facility from the Crop Backward

Lay the facility out around the daily work: mixing, irrigating, checking runoff, scouting, cleaning and fixing things. Benches go in last. The layout we build around: separate A and B stock tanks on two Dosatron injectors, a Red Lion pump feeding large PVC through 200-mesh filters, spray stakes at the pots, separate AC and dehumidification in every room, and independent sensors and leak detectors so a failure gets caught early.

Start with the water path

Trace the water from the source to the farthest pot and back out the drain, and design each step so someone can reach it, sample it and service it.

• Source water. Tap at about 250 ppm (0.5 EC, 500 scale) or lower runs straight. Above that, plan for RO to blend it down. See Tap Water, RO or a Blend.
• Nutrient injection. Our setup is two D14MZ2 Dosatrons, one for Part A and one for Part B, both at 1:128 (0.8%) and adjusted equally. During the Cake finish, Cake runs through one injector and the other is off. Mixing details are in Mixing Stock Tanks and the Dosatron components guide.
• Pump and filtration. A strainer on a 2-inch pickup, the pump, then two parallel 200-mesh filters, with unions and service valves so you can swap a screen without draining the system. Keep spare screens on the shelf. See the pump and filter assembly.
• Distribution. Size mains and zones from emitter demand (emitters × GPH ÷ 60 = GPM), not plant count. Pump and pipe sizing is in Why We Use Red Lion Pumps and Large PVC.
• Sample points. Plan a spot to catch feed at an emitter in every zone, and a way to collect runoff from a representative pot.
• Drainage. Tray drains and flood protection with backups. Water on the floor is a humidity problem and an IPM problem.

Build in redundancy where a failure costs a crop

• Cooling and dehumidification: we run separate AC and dehumidifiers rather than one combined unit. If one fails the other keeps working, and each can be serviced on its own.
• Zone isolation: a valve on every zone so one broken line doesn't shut down a room.
• Leak detection: leak sensors under manifolds, beside reservoir outlets and at tray drains, with the gateway and router on power you won't switch off.
• Independent sensors: a cheap second set of temperature and humidity sensors alongside the main controller. Ours are Govee, checked against a Vaisala handheld (how we set them up).

Leave room to work

Pumps, filters, injectors and mixing tanks need space to get a wrench and a bucket in once the rooms are full. Plan dry storage where Veg, Bloom, Cake and RunClean are kept separate and labeled. Part B pulls in moisture, so keep it sealed and out of humid rooms. Store concentrates in dark or opaque containers.

Walk the service routes with tanks, benches and equipment in their planned spots. Moving an obstruction now is easy; moving it with a full room of plants isn't.

Prove one room before you copy it

1. Run a pilot zone with the real outlets. Catch water from outlets near the start, middle and end for the same time. They should match.
2. Read pH and EC at an emitter during an irrigation, not just in the tank.
3. Log temperature and RH across the room through a full day, including lights-off.
4. Have the team shut down and isolate a pump or a line, the way they would on a bad day.
5. Fix what fails, retest it, and only then repeat the layout in the next room.

If you want us to look over a layout, see our commercial cultivation support.