Hydor 4 Watt Mini Heater (1 to 2.5 gallon)
• Extra small: easy to hide in mini tanks and bowls
• Super safe even under gravel; no damage if left running dry
• Completely submersible; ideal for use in both glass and acrylic tanks
• COMPLETELY SAFE FOR BETTA BOWLS!
• Each model increases the ambient temperature of a tank/bowl within its size range approximately 5- 10F (2.5- 5C)
• No setting necessary as this is an ambient heater that CANNOT raise temperature any more 10 degrees.