I don't think so. When my fish was dying, Dad had to take it out of the water. My brother called it a "mercy kill." :( But I don't think you should have to do it professionally.
No. Bettas sleep a lot. It's good for them
Betta dish actually don't sleep, or they'd die.
You should not put a male betta with goldfish's.They are aggressive and will fight with goldfish's goldfish give off ammonia and will kill the Betta's.
Well, for my Betta fish Sara I recommend using real plants so it could sleep there like a butterfly.
You need a de-chlorinating agent.
It depends on the type/brand of conditioner, and how much water is the Betta tank can hold.
sleep
You don't have to, but the Betta Fish likes it because they can sleep in the plant.
open
Terrapins usually sleep underwater.
you can put a betta in a 54 gallon tank
No, you should never keep a male and female betta fish together for long time periods. They should only be put in the same tank for breeding purposes and then separated after.