What temperature to use?

[Qrth]

I very recently got a betta fish + a bettaflo 2 gallon tank, along with a heater. The general temperature of the tank without the heater is 70F, while with the heater its 86F. Ive read that both of these are bad for betta fish, but I don't want to keep him in the cup he came in while I buy a new, less strong heater. Which temperature is safer to have him in for a short period of time?

 

[goatnad]

I've kept a betta in a tank with no heater at 72 degrees and had no issue. With that said betta should be kept between 78 and 82 degrees so not sure that 86 is really to far out of that range. Is your heater stuck on 86 or something? Why so high?

 

[Qrth]

I've kept a betta in a tank with no heater at 72 degrees and had no issue. With that said betta should be kept between 78 and 82 degrees so not sure that 86 is really to far out of that range. Is your heater stuck on 86 or something? Why so high?

It's only got one setting, and while it said it was good for tanks up to 5 gallons, I guess the 2 gallon tank is a too small for it to work properly for.

 

[Autumnsky]

Seems it should still turn off the heat mode if it is the standard 78F they are usually preset to. Could be broken which is bad. Can you return the heater?