It doesn't matter if you are not satisfied with my answer. You have been obsessed with the word "dragon", but you asked about "Longtan"?
Basic meaning of "pond"
1. Embankment: ~ dam. ~ weir. River. Sea.
2. pool: pool ~. Lotus ~. Fish. Reed ~.
3. In some areas, small holes are dug indoors to make a fire: fire ~
Do you think it's good for dragons to stay in these places? You can make sense if you have to understand it as "talent is lacking".
I'll give you an imposing name "Longyuan". There's a sentence in the first divination in the Book of Changes: "Jump in the deep, and see your adult". The divination is excellent. I don't know if you want to continue to struggle.