Water change?

I have a 3 gallon tank, a filter, heater and a Betta fish. I was just wondering how often would I need to do a partial water change? And a full water change?Water change?You only need to do a 25% water change once per week. Never a full water change. This will force the tank to %26quot;recycle%26quot;.Water change?I would say change 1/2 to 1 gallon of the water weekly!Water change?about one third of the water weekly and be careful not to overfeed-you should never ever do a total water change-it's very stressful for your fish and could even kill itWater change?I wouldn't ever do complete water changes. They will screw up your fish. They can't handle drastic water changes in a short period of time. As long as you do a good weekly water change and keep the tank clean it should not need full changes. Remember to always let the water sit out for at least 24 hours before you put it in the tank to not only aerate it, but to de-chlorinate it.Water change?with filter in tank, change monthly on half tank of waterWater change?a gallon or a little less than that...every week...and vacuum the gravel..you could use a siphon to vacuum the gravel while changing the water...you get them pretty cheap 4-5 bucks at any pet store..works best..and since you have a filter I would recommend a full water change...that could stress your betta...