I purchased a beautiful blue and turquoise betta about 2 months ago, maybe longer. He now lives at work where I spend most of my time and lives in a square container about 6 inches all the way around and about 7 inches in height, it may be a little bit bigger. The first few weeks that he was in his new environment he started tearing up his own fins. He looked like he'd been in a fight. He eventually stopped and his fins have almost grown back all the way. He is very territorial. If I point at him with my finger or even the end of a pen near his box he starts flarring up and swimming back and forth.
My first fish was a Betta. When I got him, he was placed in the ever-popular vase. I didn't really like him in that, and despite what the people at the pet store said, I went ahead and tried him in my 75 liter tank, with 8 fancy guppies, and a Pleco. He did pretty well. He really seemed to like it, and was not aggressive in anyway towards the other fish. As it so happens, it was quite the opposite. After about 2 weeks, I noticed a few nips from his tail, and fading color...then a few days later, he got "Ich", which he spread to 3 of my 4 female guppies. I took him out and he cleared up just fine, and the females did well also. He now resides in an 8 liter tank with occasional tankmates...as guppies are known for what they do best, reproducing, I sometimes have to move larger babies into his tank. He doesn't seem to mind, and isn't aggressive, and he really seems to enjoy the company. Well, Ralph has been doing just fine lately, and is as beautiful as ever. July 2002 will be his 5th year for me to own him.
I have a Betta, Cleo (from Pinoccio), that lives in a huge (for him) 2 gallon tank. He lives with 3 ghost shrimp, and even though they face each other down when Cleo goes to the bottom where they hang out, they get along, and since they clean the bottom, the shrimp add to the Betta's indestructable and easy-care nature. Plus the shrimp are about 40 cents each.
I work at one of the best fish shops in my area. There where 5 betta splendens in bags ready for sale, but the buyer then didn't turn up so I placed them in the two 1.5 metre plant tanks. One of the tanks had 3 of the fish in it and they where all chasing each other about for around 1/2 an hour, then they where just together looking at each other for the rest of the day. People were coming up to me asking why they were together, but they were causing no problemns so I left them. a man wanted to buy 2 of them but I didn't want to let him in case the fish did start to rumble.
I have one male betta living know in a 200 liter Southeast Asian biotope aquarium. The betta shares the tank peacefully with all of my fish except a swordtail (not from the Southeast Asian region) who he constantly nips and a firemouth cichlid (the other fish in the tank not from Asia) who he constantly engages in flaring battles with. One must always remember that bettas are much slower than other fish. When attempting to keep a betta with other possibly faster fish, you must be careful that the betta gets enough food. It took several tries to accustom my betta to the 200 liter aquarium because, living a life in a bowl and never seeing too many other fish, my bettas were usally spooked when any other fish came near them. It takes about 3 to 4 days before a betta realizes that when other fish dart towards it they don't usually want to fight, but in those 3 to 4 days, if the betta is too scared to get food they will nip there own fins for food, injuring and stressing the betta more.
As a general rule you shouldn't keep bettas together, except when breeding. Make sure there are a lot of floating plants in the tank, and place the male betta inside. Put the egg-filled female in a clear cup or jar so they can see each other, but the male cannot harm the female. Make sure the water is perfectly still. He will build a bubble nest, then go over to the female. Release her. He will then pursuade her to go under the bubblenest, and they'll tango. As she releases eggs, he will catch them in his mouth and place them in the bubblenest. When she is empty, REMOVE HER. place her in her own tank to recover for a couple days. Leave the male in with the nest, he will catch all the eggs, and, after they hatch, the fry and place them back in the bubble nest. When the fry become free swimming, take the male out because if you don't he might eat them, not knowing they are his babies! Feed the fry very small food, ground up flakes will NOT work!