Cobalt Mini-Thermal Heater 10 W (Plastic)
The all new Cobalt Aquatics MINI-Therm compact and fully submersible heaters are designed for small aquariums up to 5 gallons. Featuring a constant ON design, this heater maintains a stable temperature ideal for freshwater and saltwater environments.
The heater casing is made from thermal-plastic polymer, offering shatterproof protection. An internal ceramic heat radiator ensures even and efficient heat distribution from the heating elements.
| Model | Aquarium Size | Heating Power |
|---|---|---|
| 5 W | 1.2 gal (4.5 l) | 5 W |
| 10 W | 2.4 gal (9.1 l) | 10 W |
| 20 W | 4.8 gal (18 l) | 20 W |
This heater can raise the temperature of the water up to 10 degrees Fahrenheit above ambient.
FAQ
What types of aquariums is the 10 W heater suitable for?
The 10 W Cobalt Mini-Thermal Heater is suitable for freshwater and saltwater aquariums and terrariums up to 2.4 gallons (9.1 liters).
Is the heater safe for long-term use in small tanks?
Yes, the heater is fully submersible and made from shatterproof thermal-plastic polymer, making it safe and durable for long-term use in small aquariums.
How does the ceramic heat radiator improve performance?
The internal ceramic heat radiator provides even and consistent heat distribution, ensuring stable water temperatures throughout the tank.

Adrian Russell –
I’ve used this heater in a 2.4-gallon freshwater tank for three months. It maintains a steady temperature even during cooler nights. The plastic casing is sturdy and doesn’t crack. Easy to install and works reliably.
Penelope Burgess –
It’s perfect for my small saltwater tank. The temperature stays consistent, and I didn’t notice any hot spots. Only downside is it’s not very loud, which is good for quiet environments.
Una Hamilton –
Installed it in a terrarium last week. The heat distribution is even, and my plants are thriving. The heater is compact and fits well without blocking the view.