I have a tetra submersible 2-15gal heater and last night the water was nice and warm, when I woke up the water was cold. (Good thing I dont have my fish yet). Can somebody recommend a good heater for a 5gal tank that keeps the water at a steady appropriate temperature for my future betta. I can't wait to get him, but I'm not going to get him until I know everything is safe.
I really like my Theo Hydor 50 watt heater for my five gallon. I found it fairly cheap on Ebay. 25 watts is more than enough for a small five gallon. But I got a higher wattage in case one day I have room for a bigger tank.
It's listed on several sites as one of the best heaters to have. It is shatterproof, has the very important adjustable temperature control, and comes with a nice warranty. It lasts forever.
Here's some more information about heaters. Theo Hydor is listed on there. Clicky.
I have a 25W deltatherm and it's great so far. Heats up to 7 UK gallons, and I have it heating my 5 UK gallon tank. Fully adjustable temperature control and a good warrenty on it too. It was £16.99 from Pets at Home :)