Although my betta is fine now (it's summer here) I think I will need to heat his tank somehow in winter because my house can get pretty cold. I thought I should try and get it organised sooner rather than later and was just wondering whether anyone had used heat mats under a betta tank before and how successful it was?

I'm a bit nervous about putting a heater in a small tank (it's about 10-15 litres, I've not measured exactly) but I have a heat mat that's used to put under reptile enclosures and was thinking I could just put the betta tank on that instead. I think it raises the temperature by about 10 degrees celsius for a terrestrial setup with a sandy substrate, I'd have to see how it works on a water-filled tank first, though...
Has anyone else tried this?
Thanks

If it is a glass tank, then I can't see it being a problem. I believe I have read of people using these successfully.

If the tank is acrylic and under 5-gallons then buy a Jr. Heater from nnnnnn OR just use the reptile pad underneath. If you have a glass tank 5+ - gallon might i suggest a Penn Plax 25WATT heater. You can adjust the temp easily on them.

I dont suggest using a reptile heat mat, I almost tried that, but read in the instructions and they said not to use under a water portion of the tank cause it would crack the heating core, as well as some safty issues. there are ways of using submesable heaters in a small tank here is a Canadian link that shows that you can http://www.newsroom.net/fishkeeping/tanks.html hope this helps

thanks for that link. I asked around at a couple of aquariums and found a small heater that should be fine for the tank - I have a pretty good thermometer in there too, so will keep an eye on it and see how it goes...
thanks