My male betta crowntail lives in a 1 - gallon tank where he has a tree to rest and hide, warm water, a thermometer to monitor water temp, and food. I know Mr. Greedy is a very happy fish because he looks comfortable and is even making a nest. My problem is with the heater. Since my tank's water capacity is only 1-gallon, I supposedly cannot place a 25 Watts heater because it might cook Mr. Greedy, or so I've been told. Now, there are no smaller heaters in my area or anywhere outside ( I meant heaters with power consumption less that 25 W). I am warming the water with my own heater in the office. Problem is I get extremely cold whereas the fish is warm and happy, which I don't mind, but I would like to use a more suitable heater for him without me having to be deprived of my own heater, which is located at approximately 20 inches from the tank to keep the temp near the 80's. I have read that the types of heater I just mentioned are suitable for 1-gallon tanks. However, at the pet shops they do not agree. What can I do? Do you guys think a lamp from walmart might do the trick? I need a quick solution to this because I don't want to buy something that could potentially kill my pet. Is it true 25 Watt heaters cannot be placed inside 1-gallon tanks? I love my pet and I care for him a lot and that is why he spends his days with me in the office, where I work 8 hours every single day. When I go home I must turn off the heater, it's a company policy. The water temp obviously goes down a lot and I'm scared my fish might get traumatized or even die due to these drastic temperature changes. Any suggestions please? Should I buy the 25 W heater?
Thank you all in advance.