Betta in Community Tank Temperature Question

[PineSong]

I'm feeling a bit not so clever at the moment because I just realized today that the fish in my community tank (which I set up in hopes of making a fun environment for my betta) and my betta live at two different temps. 

My betta is 2 years old and lives in a tank with a preset 78 degree heater and even at that temp is pretty inactive--he's less active than my 3 year old 'grandpa' betta who lives in a bowl that is a bit cooler because it is lidless, even.

The water in my unheated community tank is more like 74, which is where I keep the AC set.

Not sure whether I should heat my platies and endlers to betta temps, I don't want to shorten their lifespan. What do the rest of you with bettas in community tanks do? 

[Streetwise]

I moved my Betta into an unheated community tank, and she is doing just fine.

[FrozenFins]

Bettas can tolerate a range variety of tempertures from low 70s Farenheit to Low 80s Temperture. I have a betta in a unheated tank thats sitting about roughly 70F. I have another betta thats sits at around 76 F. Both are doing fine. The one in the 76F was in a communtiy tank at that temperture with some neon tetras.

[PineSong]

Ah, good. I have kept bettas with and without heaters in the past, and thought I was doing well for them by having the heater. I also think having more to do/look at will be good for him, so the tradeoff will still be a quality of life enhancer. Thanks!