A lot of assumptions. That is if it grows, retains color, and of course time.
I see the direction you are going but this isn't similar to say, well, winning the Ford GT lottery, dropping $475K on the vehicle, resisting the urge to drive it, and then reselling it 2 years later for 1.8 million. I know that I'll get a 200% return on investment. The coral? Depends if the stars align in the hobbyist tank and the hype is real.
Never the less can't knock someone from trying. Nothing but the best to you!