I may have accidentally sucked up a baby guppy once. I'm still not quite sure if I did, or if she just died and the body was eaten before I found it. Anyway, I did a water change and the next day I couldn't find her anywhere in the tank.
Elephants have actually been found to enjoy listening to music. Elephants of different ages also tend to like different types of music, like rock, classical, etc. If I remember correctly, older elephants like classical music the best.
You can't keep those fish together, as some (like the sword tails) need hard water, and others (like the neon tetras) need soft water.
Can you tell us you ph, gh, and kh? Also, what is the biggest tank that you have space for and can afford? Once we know that, we can tell you which fish you can...
What did you have in the tank besides the gravel and black substrate? Did you have any wood, leaves, caves, anything like that? Could you move those things to the big tank, and then rescape the 6 gallon?
What about a peacock gudgeon, or a scarlet badis? I don't know if they're suitable for your water, and I'm too tired to check right now, but those were the first fish that came to mind that could live happily in a 10 gallon.
My favorite things about keeping fish are aquascaping and just watching the fish swim around and be happy.
My least favorite things are when fish get sick, and cleaning ALGAE! I hate algae so much. It is the bane of my existence.
No, nothing like that is allowed. There are some dirty jokes, friends teasing each other, things like that. Nothing really bad or insulting. Everyone is generally really friendly there, just like here.