How to heat water for water changes?

Hi all.

Sorry to keep pestering for advice, but I want to get my first betta water change properly done ^^ I'm so pleased that Rocky finally seems to be settling in, I don't want to freak him out by mucking up a water change! I never needed to heat water for my goldies water, but I assume for weekly water changes for bettas they need the new water heated to tank temp so as not to shock them? I use bottled water for my betta as my tap water has horribly high nitrates of 40ppm+. How would you advise to heat up bottled water? I thought about pouring it into a plastic bucket and leaving it in the sunshine for a few hours (probably not very much will evaporate?) or possibly microwaving it a little somehow, but not sure if this would affect the quality of the water.

Any advice would be greatly appreciated from experts! :-)

Jess ^^

if you dont do a huge water change you can do it straight from cold - it wont hurt him. I used to on the smaller tanks.

I usually do 50% changes and I fill straight from the tap, but I use hot and cold water to take the chill off my water.

The other thing I do, as atm I am having to use mineral water, I empty out the kettle and boil some (having issues with my water from the tap)

Like haych said if the bottled water is at room temp and the waterchange is under 50% just use it the way it is it wont shock them that much it actually tempts most fish to breed so doesnt do any harm.

For bigger changes I use boiled water added to water from the cold tap

I fill 2 plastic jugs leave them in the room for a couple of hours add a splash of boiling water, water conditioner, smidge of aqua salt and stir well....

Thanks for the advise you guys. I think I'll leave a bucket of water out by the window to warm up for a few hours, then add a little boiling water before water change time. Hopefully he won't spazz out too much, he was very indignant when I accidentally moved one of his plants earlier. He likes making a bed out of two of the broad leaves and sleeping in between them ^^

I use my shower to get correct temp which I suppose is okay if you have a shower LOL

Boiling a little water to add is the best way, but I don't bother with getting it accurately right for smaller water changes. Hope it went ok!