Running an aquarium looks simple but it's actually a very delicate thing that requires (at least the first few weeks) constant monitoring of the water chemistry and temperature (for tropical fish).
The kind of fish I bought is a male Betta - very territorial so the store keeps them in these little cups. There's an ongoing debate among fish hobbyists whether this is cruel or not - alls I know is the fish looked sad and sickly in there.
So here's how Monet arrived in his little cup. He looked well, but lethargic. I put him on my bookcase away from 'traffic' and drafts in my studio and got to work putting together his new ten gallon (Hilton Hotel lol) tank. It took FOUR hours and several phone calls to a friend of mine about properly setting it up. Mistakes - even small ones - can mean the death of the new fish within a week.
I waited 24 hours to let the tank cycle a bit and cleaned out some of the water in Monet's cup - I also placed him under my little desk lamp to raise the temp of his water to above 75 (which is what they prefer). After a good water cleaning in small increments he actually began to stretch out his fins and swim around a little. He was feeling better!
Finally the time came to introduce him to his new tank. This was also a long slow process which I won't bore you with, but his release was fascinating. He don't know much beyond the tiny cup he lived in and so he was a bit clumsy getting used to his new home. He had never been given a chance to swim fast or long distances so this was all new to him.
After a few weeks I'll start adding more fish over time. But for now it's just Monet, Risky and I.