Why We Use Red Lion Pumps and Large PVC for Irrigation

We run the 2 HP Red Lion RL-SPRK200: a 2-inch pickup, 1½-inch PVC and two parallel 200-mesh filters. Red Lion publishes 65 GPM at 30 PSI for it, the price is low for that much flow, and the big plumbing means that flow actually reaches the far end of the room. We've run Red Lions on zones of hundreds of plants without a failure.

To size yours, add up the emitters on the zone (emitters × GPH ÷ 60 = GPM) and pick the pump that delivers that flow at your working pressure, not by horsepower or the max-flow number on the box. For a smaller garden, downsize the pump and filters but keep 200-mesh filtration.

Our pump setup

• Pickup: 2-inch, with a strainer.
• Pump: Red Lion RL-SPRK200, 2-inch inlet and 1½-inch outlet.
• Filters: two parallel 1½-inch DIG 200-mesh filters after the pump, with service valves and unions so a screen can be cleaned without draining the system. Keep spare screens on hand.
• Delivery: 1½-inch PVC to the manifolds, then Netafim spray stakes on 5/3 tubing.

The drawings are in the pump and filter assembly and irrigation assembly guides. Treat the pipe sizes as a starting point; longer runs and bigger combined zones may need larger mains, including with the 3 HP model.

What we like about the Red Lion: the 2-inch inlet and 1½-inch outlet connect straight to big supply plumbing, the cast-iron casing and base make a solid fixed install, and Red Lion sells repair kits. The sprinkler range covers 1 HP, 1½ HP and 2 HP, and the RLHE-300 industrial model adds 3 HP. Even the 1 HP has the same 2-inch / 1½-inch connections.

Size the zone first

You need enough total flow to supply every outlet running at once while each pot still waters slowly. Count emitters, not plants: two 1 GPH emitters per pot need twice the flow of one.

These are calculated demands at the rated outlet flow, not plant-count ratings for a pump. We like the plum stakes (3.2 GPH; the grey ones are 6.6 GPH) because we can feed more plants at once and water the root zone slowly; more in Spray Stakes vs Drippers.

Check each outlet's rated pressure and measure what it actually delivers. With pressure-compensating emitters, the pump has to keep the farthest emitter inside its operating range. Inside that range they hold their rated flow, so extra supply capacity gives you even watering without forcing each outlet faster. We aim for the lowest supply pressure that still meets every emitter, regulator, valve and injector. Set irrigation run time from measured delivery; switching outlet types changes how long it takes to apply the same volume.

Flow and pressure: read the curve

Flow (GPM) is how much water moves. Pressure (PSI) is the force available to lift water, push it through the plumbing and run the outlets. A pump sold as "27 GPM, 68 PSI" doesn't deliver 27 GPM at 68 PSI. Those are two separate limits: max flow is measured with almost no resistance, and max pressure is reached at or near zero flow. The pump curve connects them, and at fixed speed a centrifugal pump delivers less water as the required head goes up.

Watch for a third number too: maximum working pressure. That's a housing or system limit, not pressure the pump can make.

A variable-speed booster such as a DAB Esybox or Grundfos CMBE can speed up to hold a pressure setting as more outlets open, up to the limit of its own curve. A fixed-speed jet or multistage pump can't. Changing its pressure-switch settings doesn't give it a new curve.

Through the same open flow path, more flow needs more pressure difference. Assuming turbulent friction dominates, with no elevation change or pressure-regulating outlets, friction loss rises with the square of flow:

That's an illustration, not a pump rating. Doubling the pressure difference gives about 41% more flow; doubling flow takes four times the pressure difference. The same rules apply to a Red Lion: closing a valve adds resistance and cuts flow, and enlarging restrictive plumbing lowers the pressure needed for the same flow. See KSB on system curves and speed control.

Big PVC keeps the flow

We start with properly sized PVC, fittings, valves and filters instead of using extra pressure or a jet pump to push through undersized plumbing. At 20 GPM, Rain Bird's Schedule 40 PVC chart gives these losses per 100 feet of straight pipe:

Fittings, valves, filters and elevation add their own losses on top. Source: Rain Bird PVC friction-loss chart.

• Suction side: restrictive suction plumbing can starve the pump. Check reducers, hose fittings, valves and filters along the whole route.
• Vertical runs: bigger pipe cuts friction on the way up, but the lift itself still takes head whatever the diameter. Size the pump for elevation, remaining friction and outlet pressure together (how elevation and friction add up).
• Port size: a pump's published curve already includes its own ports. A short 1-inch connection doesn't lose what 100 feet of 1-inch pipe does, and port size alone doesn't set capacity. Large external pipe still helps any pump. For us it's the combination that works: big connections, a suitable curve and low-restriction plumbing.

Red Lion delivery at working pressure

All six Red Lion models at the same discharge pressures. Flow is in GPM.

These are manufacturer figures at the pump, before your downstream losses. The RL-SPRK table is at 5 feet of suction lift; the RLHE-300 page lists its figures by discharge pressure without stating that lift, so don't read the 3 HP row as a same-installation test. BR models have brass impellers.

Notice how hard the 1 HP and 1½ HP models drop between 30 and 40 PSI. Keeping avoidable losses out of the plumbing makes a big difference on those. And even 1 HP can be more pump than a very small garden needs; pick by zone demand and pressure, not horsepower. Red Lion models and specifications.

How other pumps compare

Max flow and max pressure are separate limits, not simultaneous delivery. Connection sizes are nominal. Grundfos values marked * are approximate readings at the ends of its published curve, not stated maximums. DAB pressures are converted from maximum head using the 220–240 V sheets. These pumps have different power ratings and controls, so this isn't an equal-horsepower test; compare flow at the head your installation needs, and confirm the exact regional model and thread type.

At working pressure: EcoPlus publishes 14 GPM for the Elite Jet HGC727190 and 16.1 GPM for the Elite Multistage HGC727182 at about 65 feet of head (roughly 28 PSI). DAB's tables show about 23.8 GPM at 39 PSI equivalent for the Esybox and 13.2 GPM at 44 PSI equivalent for the Mini 3. Compare that with the Red Lion chart above. Head equivalents and discharge pressure need adjusting for inlet conditions when you size a real installation.

Against Goulds at the same horsepower and 5 feet of suction lift (flow in GPM; connections inlet / outlet):

The 3 HP Goulds GT30 uses 1½-inch connections and delivers 105 / 92 / 73 GPM at those pressures and 5 feet of lift; the RLHE-300 figures don't state the same lift. The Goulds pumps deliver more, which shows port size alone doesn't decide performance. We still size from the curve. The Red Lion wins for us on useful flow, a 2-inch intake and a much lower price (see below). Goulds performance table.

Sources: Red Lion sprinkler pumps, Red Lion RLHE-300, Leader technical catalog, EcoPlus Elite manufacturer brochure, DAB Esybox technical data, Esybox Mini 3 technical data and Grundfos CMBE technical data.

What they cost

Prices checked October 23, 2026. These are single retailer listings, not a lowest-price survey, and they exclude tax, shipping, installation and any controls you need separately. Prices and availability change. The Goulds GT20 was listed at $1,125.60, checked October 25, 2026.

The products aren't equivalent. The Esybox includes variable-speed control, sensors and an expansion tank, which is worth paying for in installs that need them. The Red Lion is a plain pump that we tie into the irrigation system's own controls and protection. For our design, lots of flow at a modest price is what we want. Budget on the complete installed system; purchase price doesn't tell you electricity use or lifetime cost.

Scaling up: 3 HP or two 2 HP pumps

The RLHE-300 3 HP industrial sprinkler pump has a 230 V motor, a heavy cast-iron housing and 2-inch suction and discharge. Its published max flow is 124 GPM and max pressure 59 PSI, again separate limits. Size it by the zone's flow and total head, and size the pickup, mains, filters and valves to match.

The other route is multiple RL-SPRK200s, either one pump per zone group or matched pumps in parallel into a properly sized common main. At the listed prices, two 2 HP pumps come to $939.98 for the pumps alone, against $1,689 for the 3 HP at the cited retailer. Add the extra plumbing, controls, electrical work and protection before you compare.

For parallel pumps:

• Give each pump enough suction supply, a check valve on its discharge and isolation valves, and coordinate the controls.
• Size shared mains and filters for the combined flow.
• Parallel pumps add flow at a common head; they don't add pressure, and system flow won't necessarily double.
• Check the combined curve against the system, including running on one pump. See parallel-pump operation.

Fixing uneven delivery

Run the whole zone and catch water from outlets near the start, middle and end for the same time. For short irrigations, include the real start-and-stop cycle, since lines filling and draining change what each pot gets. Room-level checks are in What to Check When Part of a Room Misses an Irrigation.

• One outlet low: check the stake or emitter, microtube and connection for blockage or kinks. Clean or replace it, flush, and retest.
• A whole downstream section low: check its valve and branch for restrictions. Measure pressure while flowing at the branch entrance and the far end. Fix an undersized or blocked supply before extending run time.
• Everything low: check reservoir level, pickup submergence, intake screen, suction-side air leaks and priming. Then check the filters and whether the pump can supply the full zone at the required head.
• Strong pressure before a filter, weak after: measure the difference with water flowing. Clean a dirty screen; if a clean filter still loses too much, check its flow rating and layout.
• Better when fewer outlets run: total demand or a shared restriction is more than the supply can handle. Split the zone, improve the plumbing, or choose a pump that delivers enough at the calculated head.

After any repair, repeat the catch test and reset run time from measured delivery. Lengthening run time before you fix uneven distribution just overwaters the plants that were already getting enough.

Follow the Red Lion installation manual for suction plumbing and priming. Your controls need to prevent dry running and long runs against a closed discharge valve.