I think the biggest thing with all these threads is none of these tanks are gonna be a reality for about 3-7 years. Why not setup a reef tank, small coldwater tank and fowler right now? That way you'll have a base to go off of. No one on here has any idea of your experience other than what you have said.
the octopus tank does not seem realistic, that tank size seems to small. And maintaining that species seems like something best left to public aquaria.
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