There aren't that many 2.5 gallon tanks out there, so my own suggestion is anything over 3 gallons. It also gives a little wiggle room for gravel and plants. That being said, I have kept fish just as well in 1 gallon tanks, and so have many of the members of this forums. In the end, it's all up to you.
Fish do not get happy. They do not have the emotions that humans assign to them. They can be healthy, excited, agitated, hungry.. but happy and sad are human concepts. If a fish is healthy, active, responsive to stimuli, eating and pooping, this is as close to happy as a fish can get. We, as their caretakers, have to watch their water, make sure it is safe for them, and as long as it is, they will be healthy. You can keep a betta healthy in a 5 gallon tank, or a 1 gallon bowl, whatever you are comfortable with, as long as you give them the proper care.
Sometimes we need to keep our bellybuttons under our shirts, cause those things can be really ugly...
Last edited by Olympia; 09-03-2012 at 04:03 PM.
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