Instruct: Classify a given review into positive or negative sentiment.
Query: Works fine for a 1-gallon tank

I bought this little heater for a one-gallon tank for my beta. I bury the heater under the rocks in the bottom of the tank. It works fine, keeping the water between 75 and 85 degrees Fahrenheit most of the time. If the apartment is cold, the water can get down to 72 degrees. If the apartment is warm, the water can heat up to 90 degrees. We plugged the heater into a power strip with a switch so that we can easily turn the heater off on warm days. Great so far.