Max and lowest tank temp

[Fieldz]

My betta tank sometimes get to 86F . Is this fine or I need to cool it with an ice bottle?

[SnowySurface]

I would try to cool the temp down by 4 degrees since 78-82 is the range you should aim for. Is there a reason for the high temp water?

[tf1265]

If it "sometimes" gets there, it is OK. Bettas can tolerate that temperature for a short amount of time. If it regularly gets that high or stays that high for more than a day or two at a time, then you need to think about finding a way to cool it down. Ice bottles are risky as it's a pretty severe temperture you're adding. Pointing a fan at the tank sometimes works and is more consistent.

[Fieldz]

Sometimes here in Brazil we get 40c temps lol. That is like 93Fahrenheit I think, not sure...

[Kytkattin]

Mine regularly stays at 86. My boys have no problem with that. It also depends on if the tank is cooler at the bottom than the top. If they can go down, the surface can be 100+ because they can go lower to get cool, just like what happens in the wild. However, with a manually heated tank you will probably find that doesn't happen.