Vendor Teardown 07 — Irrigation + Water Treatment

Source: 06_irrigation_wetroom.jpeg + 07_pricing_offer.pdf

Read (equipment spec)

Pricing offer — Irrigation

Pricing offer — Water Treatment

Findings

Finding 1 — Autogrow IntelliDose + Peripod M4 is legit mid-tier

Autogrow is a New Zealand hydroponics automation brand; the IntelliDose is a dedicated nutrient mixing + irrigation controller that handles EC/pH target matching, daily schedule, and 4-part (A/B/pH-up/pH-down) dosing. Peripod M4 is their 4-channel peristaltic dosing pump module.

Pros:

• Legitimate commercial dosing — this is what small-to-mid commercial operators actually use.
• Handles EC/pH loops with real instrumentation (not a poor-man's DIY Atlas Scientific setup).
• 5+ year lifespan in normal operation.
• Resells / supports across EU via agricultural distributors.

Cons:

• Cloud integration via Autogrow's portal. Local-only operation is possible but limited. A cloud outage doesn't stop the controller running its current schedule, but does stop remote monitoring and schedule updates. See 08_sensors_controls.md for the broader cloud-dependency discussion.
• Limited integration with third-party control layers (Home Assistant, TrolMaster) — the IntelliDose is its own island.
• Pricey replacement parts (peristaltic tubing, motor cartridges).

Verdict: Of all the vendor's equipment choices, the dosing stack is the one most worth keeping. The Autogrow is defensible.

Finding 2 — "Capillaries" and "Pipes" are €0 / "buy locally"

These two lines are marked as not included in the €82 584 total. That means:

• Drip lines, stakes, emitters from each table to each plant — the customer buys locally.
• Main water supply pipes from the wet room to each growing room — the customer buys locally.

At 3 tables × 2 flowering rooms × ~40 drip stakes per table = ~240 drip stakes, plus manifolds, PEX pipe runs, quick-connects, and solenoids. Realistic cost: €800–1 500 in materials, plus labour. This is a hidden scope gap the customer will feel on day 1 of install.

Finding 3 — RO 250 L/h at €4 499 is commercial mid-grade

€4 499 for a 250 L/h commercial RO unit with controller software is consistent with a mid-tier European or Chinese commercial RO (e.g., Grunbeck, BWT small commercial, or a Chinese commercial OEM). Genuine Bluegold / Aquafox / HM Digital commercial RO at this capacity runs €3 500–6 000, so the pricing is defensible.

Water demand math (from ../pitch/customer_pitch.md / ../../../grow1/docs/diy_proposal/04_irrigation_kept.md):

• Flowering transpiration × 2 rooms: ~540 L/day
• • 30 % drain-to-waste runoff: 700 L/day flowering irrigation
• • Vegetative: ~100 L/day
• • Mothers/clones: ~50 L/day
• • Cleaning / RO waste concentrate / misc: ~100 L/day
• Facility water demand: ~950 L/day

RO at 250 L/h × 60 % realistic duty = 3 600 L/day production capacity. Massively oversized — which is correct: it lets you fill the 780 L permeate tank in bursts and handle the RO waste ("concentrate") stream that's 40–50 % of the input. At 950 L/day consumption and 50 % recovery, incoming tap needs to supply ~2 000 L/day. Check Malta water supply pressure and flow rate at the lease site.

Finding 4 — Nanobubble oxygenator at €3 900 is a premium (but genuine) call

25 ppm dissolved oxygen in 45 min is consistent with a real nanobubble generator (Mazzei / Moleaer / Chinese OEM). Sub-100 nm bubbles stay in solution for hours, giving DO levels 3–4× a standard aerator and suppressing root-zone pathogens (pythium, fusarium).

This is the single best line item in the vendor offer. Worth keeping in the counter-proposal. Building a DIY equivalent would require a Venturi injector + pressurised oxygen source + the right bubble-generation head, and you'd end up spending ~€2 500–3 500 anyway. Just pay the €3 900.

Finding 5 — 780 L permeate tank with UV sterilizer at €1 499

UV sterilisation of stored RO water is good practice — stored RO water slowly recontaminates from tank surfaces and pipes, and UV-C on the supply line kills pseudomonas / pythium spores before they reach the dosing skid. €1 499 for tank + pump + UV + level sensors is fair.

Finding 6 — No fertigation-tank temperature management

Malta groundwater is warm in summer (22–26 °C) and cold in winter (12–14 °C). Root-zone temperature matters — below 18 °C root uptake collapses, above 24 °C pythium risk climbs. The wet room needs either:

• A tank-heater (1 kW titanium immersion heater, ~€80) for winter
• A tank-chiller (Teco 200 W aquarium chiller, ~€180) for summer
• Or both, on a thermostat

Not in the €82 584 offer. Another hidden scope gap.

Finding 7 — No EC/pH inline sensors downstream of dosing

The IntelliDose handles EC/pH at the mixing tank. But there are no inline sensors downstream at the irrigation manifold to verify that what's actually hitting the plants matches the setpoint. Commercial fertigation best practice is to have a second EC/pH probe at the drip-line entry, with HA or SCADA alerts if it drifts from setpoint (indicates a blocked line, pump failure, or mixing-tank contamination).

Downstream inline sensors are ~€400–800 extra and not in the offer.

Confirmations still needed from vendor

1. Autogrow model numbers (IntelliDose II? Original IntelliDose?) and firmware version.
2. RO brand and model — is it rebranded Chinese or a known European brand?
3. Nanobubble generator brand / model — Mazzei, Moleaer, or Chinese OEM?
4. Is the drip-line and main-pipe material included in the "Extras" €1 560 line or genuinely "buy locally"?
5. Winter fertigation-tank heating plan?
6. Inline downstream EC/pH monitoring?