Fluval P25 Pre-Set Aquarium Heater
Designed for aquariums up to 6 US gallons, the all-new P series heaters are fully submersible and offer a safe shatterproof polymer construction. They are equally convenient, featuring a pre-set temperature and LED running lamp.
- An ultra strong and durable polymer casing surrounds the heater, protecting it (and tank inhabitants) from damage.
- With no adjustment necessary, the heater is pre-set to maintain a temperature of 24 – 26 °C (76 – 78 °F).
| Specification | Detail |
|---|---|
| Heating Range | 24°C – 26°C (76°F – 78°F) |
| Compatible Tank Size | Up to 6 US gallons |
| Construction Material | Shatterproof polymer |
| Heater Type | Pre-set, fully submersible |
FAQ
What is the temperature range maintained by the Fluval P25 heater?
The Fluval P25 heater is pre-set to maintain a temperature between 24°C and 26°C (76°F – 78°F).
Is the heater safe for fish and the aquarium tank?
Yes, the heater features a shatterproof polymer casing that protects both the heater and tank inhabitants from damage.
Can the temperature be adjusted after purchase?
No, the Fluval P25 is pre-set and does not require any adjustment for temperature control.

Neil Rees –
The P25 heater has been running smoothly for three months. My 6-gallon tank stays at a consistent temperature, and my fish seem more active and healthy. The LED light is helpful to know when it’s on, and the plastic casing feels sturdy.
Simon Morgan –
Easy to install and works exactly as described. No issues with temperature fluctuations. The heater stays in place and doesn’t make noise. I appreciate the pre-set function—no need to adjust anything.
Una Paige –
I’ve had several heaters before, but this one is the most reliable. It keeps my tank warm without overheating. The polymer body is durable and looks good in the tank.