This is a high quality original spec replacement 25w glass heater manufactured by Aqua One for use with any aquarium of up to 25 litres in capacity.
Aqua One's Glass Heaters are extremely robust in use and under normal circumstances completely reliable.
As ever with an aquarium heater, only ever switch on whilst fully submerged in your aquarium.
The 25w glass heater is thermostatically controlled and easily adjustable to the exact temperature requirement of your aquarium, meaning that it is literally a "fit and forget" item
When installing your new aquarium heater it's best to leave the new heater sitting in the aquarium for about 5 minutes in order to acclimatise to the current water temperature before plugging in.
Don't worry if the heater appears to switch on and off in use... this is perfectly normal.
Whilst Aqua One Glass Heaters are ultra reliable, with many tens of thousands in circulation, we still can't stress enough the importance of keeping a spare. Your aquarium inhabitants will start to suffer from temperature change far quicker than poor water quality and having a spare heater on hand will avoid unnecessary suffering and discomfort to your precious livestock