Heater(s) for 10 Gallon Tank?

[fromidam]

Hey there all =)

My betta Elrod (I did not name him for the record, he was my group's pet fish at summer camp and I brought him home afterwards) is currently in a 1/2gal container, and I've found what looks like a nice 10 gallon tank to upgrade him to that I'll hopefully be picking up this weekend. Amongst the things I'll need to buy for the upgrade is a heater, which is what I'm wondering about.

When I was in one store today I found several heaters which all had different wattage (for the tank sizes), but didn't buy any because it was at a different store than where I found the tank and at the time I didn't know what size I would be getting. After doing some reading online I'm a little concerned about heaters in general, as apparently they can cause hotspots, and the tank I'm looking at doesn't have a water pump or anything for water circulation (which I'm to understand bettas don't need or particularly like anyway).

What I'm mostly wondering about is:

• Are hotspots something to worry about when there isn't much water movement?
• For temperature monitoring, where in relation to the heater should I attach the thermometer?
• Might I be better to, say, buy two 5 gallon heaters and put them in opposite corners of the new tank?
• The clerk at the store said that he usually suggests buying a heater for a tank size up from what you have (so buy a 10gal heater for a 5gal tank, etc.), but I don't remember if I mentioned that I have a betta to him. Anyone have any input on this?

Thanks for your help! ^_^

-Max

[katydidmischief]

I have a 50watt heater in my 10gallon that's adjustable and it was around 20 bucks on sale; Hydor THEO is a good one to get. I wouldn't recommend anything preset as they don't typically work all that well.

As for the water circulation, if it's placed under a filter, the warmer water will circulate that way; if you don't have a filter, maybe get a bubbler--it'll help get some movement in the water.