I've seen a lot of Bettas (Siamese Fighting Fish, right?) sold in shops & markets in basically nothing bigger than a jar. The blurb goes that their natural habitat is small and the water quality isn't great. Then I start to do some research on the net and see that they should be treated like any other tropical - filtration & heating essential.
I am a clueless newbie, only getting my first tank a few days ago and I still haven't added water to it yet, but I'm curious to figure out what is the truth here....
A good minimum tank size for a betta is 2gals+, but the bigger you can get the better, male bettas don't make very good community fish so if you do get one its best to keep it on its own- never mix male and female bettas or male and male bettas, you can keep females together but they need to be in fairly large groups to work.
Heating and filtration depends alot, if you don't fancy doing 2-3 100%water changes with dechlorinator weekly then a filter is advised as once it cycles it enables the tanks water quality better for longer(you will still have to do water changes with dechlorinator but only 25% once a week), bettas are quite exceptional tropical fish as they are one of the few tropical fish that can live without filtration as long as their water is kept clean on a regular basis.
Heaters are mainly there to
a. Heat the tank to prefered tropical temps if your home is not warm enough to keep the tank at a steady tropical temp, and
b. To prevent temperature fluctuations- fluctuations in tank temp can be very stressful for fish, one of the problems of unheated tanks is that when night comes and the air cools down it can make the tank temp fluctuate alot if it does not have a heater for example, tropical tank heaters are designed to keep the tank at a constant steady temp.
If you get a tank smaller than 5gals it can be very difficult(but not impossible) finding a heater or filter small enough for it as most filters and heaters are designed for tanks 10gals+ so you need to take this factor into consideration when you buy your tank
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