Which pump for a gargoyle or wall spout? Simple calculation of head height and flow rate

A successful gargoyle produces a clear, steady stream of water that falls in the right place with a soothing sound. An unsuccessful gargoyle produces a jet that dribbles down the wall or, on the contrary, sprays the terrace. Everything comes down to one setting: the right flow rate at the right height. Here's how to choose the right pump without making a mistake, whether your spout is a stone lion's head, a resin mask, or a simple stainless steel blade.

1. Measure the total dynamic head

The only measurement that matters for a pump is the height difference between the surface of the water where it draws water and the water outlet point. The depth at which the pump is placed does not matter: what matters is how far it has to "raise" the water above the level of the basin.

• Measure the height between the water level and the gargoyle's opening. Example: 90 cm.
• Add a margin for losses in the pipe and elbows: approximately 10 cm per meter of narrow pipe and per tight elbow. For a classic wall gargoyle, a 50 cm margin is sufficient.
• You obtain the calculated height: here, 1.40 m.

2. Choose the flow rate according to the desired effect

The flow rate depends on the size of the opening and the desired result. A flow rate that is too low produces a stream that "sticks" to the wall and runs along the stone. A flow rate that is too high projects the water too far and causes the basin to overflow.

Indicative values from our installations. For a wide sheet of water, calculate based on the width in centimeters: see our dedicated article below.

3. Reading the pump curve

This is the most common mistake: buying a “1,000 L/h” pump expecting to get 1,000 L/h at the spout. This figure is the maximum flow rate at zero head. At 1.40 m, the same pump delivers only a fraction of that amount. Always check the flow/head curve published in the technical data sheet: find your calculated head and read the corresponding flow rate. It should fall within the range in the table above.

If the calculated flow is borderline, choose the next model up: it is better to have a slightly more powerful pump that can be throttled with its regulator than a pump operating at its limit, which will produce a weak stream as soon as the foam begins to clog.

4. Installation

The reservoir

The pump must always be submerged. If the gargoyle empties into a pond, place it at the bottom on a flat stone, away from silt. If it empties into a bowl or small basin, check that the water volume is sufficient to compensate for a day's evaporation in summer: a basin that is too small will empty and the pump will eventually run dry.

The hose

Use a flexible hose with the same diameter as the pump outlet, then reduce it only at the gargoyle connection. Run it behind the wall or through the joints, with as few bends as possible. An opaque hose limits algae growth inside.

Final adjustment

Start at maximum flow, then gradually close the regulator until the stream falls exactly in the center of the basin. Adjust it again after a week: the pump foam begins to clog and the flow decreases slightly.

5. Maintenance

• Rinse the pump foam every two to four weeks during the season.
• In areas with hard water, descale the gargoyle's mouth once a year with white vinegar.
• In winter, remove the pump, and empty the gargoyle and hose: water that freezes inside a stone or resin piece can crack it.

Also worth reading

Would you prefer a wide waterfall? How to choose a pump for a water blade.

READ THE ARTICLE

Frequently asked questions

— Why does the sheet of water run down along the wall?

The flow rate is too low for the head, or the spout is clogged with limescale. Clean the pump foam and spout, then open the regulator. If it is already fully open, the pump is undersized.

— Can a solar pump supply a gargoyle?

For a small, low gargoyle, sometimes. But most solar pumps lack sufficient pumping head and stop as soon as the sky becomes cloudy. For a steady sheet, a 230 V pump remains more reliable.

— Is the gargoyle noisy at night?

The noise depends on the drop height and flow rate. Slightly reducing the flow or letting the sheet fall onto a submerged stone noticeably softens the sound. A timer also allows you to turn off the water feature at night.

— Can the filtration pump be used to supply the gargoyle?

Yes, using a branch fitted with a valve, provided the pump has enough spare head. Otherwise, a small dedicated pump is easier to adjust and does not weaken the filtration.

In summary

• Calculated head = water level → spout + approximately 50 cm.
• Flow at this head: 300 to 800 L/h depending on the spout and effect.
• Read the flow/head curve, not the maximum flow rate.
• Flow regulator essential; store dry over winter.

Last updated: September 28, 2026.