The Tsurumi PU series is a submersible vortex pump for water carrying solids — drainage on fish farms, ponds and aquariums where feed, faeces, shell or debris would block a standard drainage pump, along with raw sewage and general wastewater. The vortex impeller sits recessed from the flow path, so solids up to 46 mm pass through the volute rather than the impeller, and the lubricant is liquid paraffin rather than mineral oil, so a seal failure won’t contaminate the water around live stock.
Key Features
- Vortex impeller passes solids to 35 mm (40/50 mm bore) and 46 mm (80 mm bore) — where a standard drainage impeller typically passes 10 mm or less
- Engineering resin and 304 stainless steel construction resists corrosion, including seawater and rainwater duty
- Liquid paraffin lubrication instead of mineral oil — safe for fishponds, waterscapes and aquaculture if a seal ever fails
- Dual silicon carbide mechanical seals, oil lifter and anti-wicking cable entry for continuous submersed service
- Single-phase 240 V models (0.25 / 0.4 / 0.75 kW) are RCM certified; three-phase models to 3.7 kW
- Automatic float-switch (PUA) and auto-alternation versions available for unattended and duty/standby operation
- Back pull-out design for easy inspection and maintenance (excludes the 0.15 kW model)
Applications
- Fish farms, hatcheries and RAS facilities — purge water, backwash and floor drainage carrying feed, faeces or shell
- Ponds, waterscapes, waterfalls and aquariums
- Sewage treatment plants and septic tanks
- Equalisation and wastewater measuring tanks
- Seawater and rainwater pumping
- Construction wastewater drainage and general water transfer
Technical Details
| Discharge Bore (mm) | Manual Model | Automatic Model | Motor Output (kW) | Phase | Starting Method | Solids Passage (mm) | Max Flow (L/min) | Max Head (m) |
|---|---|---|---|---|---|---|---|---|
| 40 | 40PU2.15 | 40PUA2.15 | 0.15 | Three | D.O.L. | 35 | 190 | 5.5 |
| 40 | 40PU2.25S | 40PUA2.25S | 0.25 | Single | Capacitor Run | 35 | 215 | 6.8 |
| 40 | 40PU2.25 | 40PUA2.25 | 0.25 | Three | D.O.L. | 35 | 215 | 6.8 |
| 50 | 50PU2.4S | 50PUA2.4S | 0.4 | Single | Capacitor Run | 35 | 270 | 9.6 |
| 50 | 50PU2.4 | 50PUA2.4 | 0.4 | Three | D.O.L. | 35 | 270 | 9.6 |
| 50 | 50PU2.75S | 50PUA2.75S | 0.75 | Single | Capacitor Run | 35 | 360 | 12.5 |
| 50 | 50PU2.75 | 50PUA2.75 | 0.75 | Three | D.O.L. | 35 | 360 | 12.5 |
| 80 | 80PU21.5 | 80PUA21.5 | 1.5 | Three | D.O.L. | 46 | 780 | 15.2 |
| 80 | 80PU22.2 | 80PUA22.2 | 2.2 | Three | D.O.L. | 46 | 820 | 17.8 |
| 80 | 80PU23.7 | 80PUA23.7 | 3.7 | Three | D.O.L. | 46 | 950 | 23.9 |
Max flow and max head are taken from Tsurumi’s 50 Hz performance curves — use the curve below to check your exact duty point.
Performance Curve
Downloads
Frequently Asked Questions
What’s the difference between the manual and automatic models?
Automatic (PUA) models carry an integrated float switch, so the pump starts and stops with the water level and won’t run dry — ideal for unattended sumps and pits. Auto-alternation versions share the load between two pumps in duty/standby installations. The video below shows how both work.
Is it safe to use around live fish?
Yes. The lubricant is liquid paraffin rather than mineral oil, so a seal failure won’t contaminate the water — the reason the Tsurumi PU is rated for fishponds, aquaculture and aquarium duty.
Should I choose the PU or the PN series?
Pick the PU when the water carries solids — its vortex impeller is the clog-resistant option. On cleaner drainage the semi-vortex PN series gives more head per kilowatt, and for dedicated seawater duty see the titanium TM series.
Which model do I need?
It comes down to your duty point — flow, delivery head, pipe run and what’s in the water. Send us those details and we’ll confirm the right model, price and lead time.
