Fluval Pre Set Aquarium Heater 10w P10

Description

Fluval Pre Set Aquarium Heater 10W P10 — Fixed 24–26 °C submersible heater for nano tanks up to 10 litres

A betta bowl or a 10 litre nano does not need a dial, it needs a heater that holds tropical temperature and cannot be knocked off it. Fluval Pre Set Aquarium Heater 10w P10 (SKU: MRN23) is the smallest of Fluval’s P-Series, a 10 W fully submersible heater preset to maintain a consistent 24 to 26 °C (76 to 78 °F) in fresh and saltwater nano aquariums up to 10 litres (3 US gal). The element sits inside a strong, shatterproof polymer casing that protects both the tank and its inhabitants, with no glass tube to crack, and an LED lamp lights whenever it is on.

The P10 measures just 13.5 × 2 × 1.5 cm, mounts with suction cups and is waterproof, so it can be positioned horizontally low in the tank or tucked into the filter chamber of an all-in-one such as the Fluval Spec, which Fluval markets its P-Series heaters for. Fluval notes that if the gap between room temperature and the preset exceeds about 8 °C the heater may lack the capacity to reach it, in which case the 50 W P50 (MRN26) is the better choice; the P25 covers tanks to 25 litres. Fluval backs the P-Series with a two-year warranty. The heater must never be operated outside water.

Usage & Application

When to Use

• Betta and nano tanks: Aquariums up to 10 litres that need stable tropical warmth without adjustment.
• All-in-one kits: Small enough for the rear chamber of a Spec or similar desktop aquarium.
• Shrimp and fry tanks: A low-wattage heater that cannot overshoot in a small volume.
• Fresh or saltwater: Rated for both.

Installation Guide

• Position: Press the suction cups onto the glass at the rear of the tank, near the filter flow, fully submerged and never below the MAX line marked on the unit; maximum depth 0.9 m.
• Wait before plugging in: Leave it in the water for 10 minutes to acclimatise, and form a drip loop in the cord.
• Check with a thermometer: The red lamp shows it is heating; confirm the water temperature with a reliable thermometer.
• Maintenance: Unplug and let it cool for 30 minutes before removing; clean with a vinegar soak and fresh-water rinse, no chemicals.

Product Specifications & Highlights

Key Features

• Preset 24–26 °C: No adjustment required; switches off at temperature.
• Shatterproof polymer casing: Protects tank and inhabitants from damage.
• Fully submersible and waterproof: Easy positioning anywhere in the tank.
• LED running lamp: Shows when the heater is working.
• Compact 10 W: Sized for aquariums up to 10 litres.

Product Details

• Brand: Fluval
• SKU: MRN23
• Barcode (GTIN/UPC): 0015561107433
• Product Type: Heating & Cooling > Submersible Aquarium Heaters
• Model: Fluval P10 Submersible Heater (item A743)
• Wattage: 10 W
• Preset Temperature: 24–26 °C (76–78 °F)
• Tank Size: Up to 10 L (3 US gal)
• Dimensions: 13.5 × 2 × 1.5 cm
• Mounting: Suction cups; fully submersible to 0.9 m
• Warranty: 2 years
• Range: P10 (10 L), P25 (25 L), P50 (50 L, MRN26)
• Target Environment: Freshwater and saltwater nano aquariums