How repeatedly should i rework the hose down surrounded by a betta bowl lacking a filter?

I just got the Betta five days ago and I have ordered a 2.5 gallon cistern with a filter and heater for it. It should come between friday and wednesday, should I bother changing my bettas river before then?
I would revise at least 25% of the water between now and later if possible. You could possibly use a siphon to remove the water without affecting the fish.
It depends on how big the "bowl" is. Hopefully you are not keeping it in the cup it came in, but I'm going to purely use common sense and guess you are not.

If the bowl is one gallon or more, you should change it once a week.
Any smaller and you're looking at maybe every 3 days.

Good choice on a filter and a boiler, that's making a smart step forward into keeping your pet happy and safe.

Please make certain to cycle your tank before adding any live animals =]
um why did you buy the betta earlier you had a tank

it really depends on his current living conditions
I merely keep mine in a bowl without any filter or radiator. It is doing pretty well. I change water every 2-3 weeks.
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