Irrigation/Fertigation Layout/Specs/Price?

Hey all,
I’m building our a 1600 sq ft grow room and have been to the moon and back with many vendors on plans and schematics for everything from electrical to irrigation. I did a forum search and didn’t return any threads but maybe those of us who’ve been down the ‘build out’ road can compile a thread of information on recommendations, various setups and pricing ranges for irrigation/fertigation methods for the community?

I haven’t pulled the trigger yet but for the 1600sq ft room, I’m outlining x6 4ftx32ft tables with x8 4x4ft LED lighting footprints above each and 6 plants per light. That delivers the below specs:

-Plant Count = 288
-Light Count = 48
-Amperage used on 220v fixtures = 140A
-Lights per 20A breaker (2.9A each 220v fixture) = 5
-x2 36,000 BTU minisplits ($8,000 equipment + install)

A couple questions:

-Does anyone have a solution to warm water inline before it gets to fertigation so I can come straight out of the well without housing reservoirs in-house? I don’t think there’s a heater capable of hitting the target GPM flow required to feed 144 plants (1/2 the room at a time) with starting water temp of 43 degrees.

-Who has knowledge on reservoirs, pumps, gpm, dosatron irrigation and fertigation?

An tankless water heater. Kind of expensive, but instead of hot water heater tank, it’s a small box maybe 18” square. It will heat an endless amount of water in seconds to the exact temp you request. I’ve also been in the irrigation business for golf course and residential properties for over 25 years. Fell free to ask if ya have irrigation questions.


Thanks Nug! I will have questions once I receive these follow up equipment quotes. I’ve looking into those tankless water heaters but they seem to be maxed out with our target GPM and temp settings. Plus they need multiple 20/40A breakers to run. At least there’s an option though.

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A gas or propane tankless water heater would be more economical and would have no problem producing the warm water that you need…
The electric tankless water heater’s are useless and have flow restrictions…
They suck and are a waste of money…

How about this: get a hot water heater and put it on the lowest setting ie 90 degrees F. Then get an in-line temperature control valve which mixes hot/cold water ratios to a desired temp output of 68 F. From there we go into the fertigation skid (sucks up nute combinations) and goes to our irrigation lines. My thoughts and questions:

STEP 1. Water Sources HOT / COLD
-Water heater set to lowest setting -
-Cold water coming in at 43 degrees F -
Both flow to temp set mixing valve at 68 degrees F In-Line Thermostatic Mixing Valve [MixingValveCRP-050] | DudaDiesel Biodiesel Supplies
Netafim Disc Filters ensuring no particulate gets into the system.
Water temp thermometer ensuring we’re at or near 68 degrees.

STEP 2. Fertigation Flow Control
System Type: NDS Kits Inlet / Outlet Size: 3/4"
Water Flow Range (Min‐Max GPM): 2 to 10 System Size: Lo‐Flo
Water Pressure Range (Min‐Max PSI): 55 to 85 Irrigation Method: DTW
Overall NDS System Length(inches): 235.59 Nutrient/Feed Type: LIQUID
-How do we turn the system on/off? If on/off control is here, how do we alternate feeding days downstream?

STEP 3. Fertigation
-Dosatron Skid in rooms #1 & #2

STEP 4. Irrigation Flow Control
-How do we turn the system on/off per room? If on/off control is here, how do we keep nute/water from sitting in mixing reservoirs upstream in the fertigation skids?

STEP 5. Irrigation Per Room
-Low volume zone control kits (Netafim 24V S-80 VLV 3/4 FLTR 45PSI)
-PVC up wall to ceilings and back down to tables (leaving floor space for cart transportation and traffic
-PVC line down table to manifolds?
-manifolds ensuring constant pressure to each out line?
-Polytube to each plant dripper ring (Netafim NETBOW 10" 8 OUTLETS 0.53GPH @ 14.5PSI)

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