aquapod, oceanspar, a seastead can also have integrated cages... so this is again an example where the business model will influence the form of the seastead.
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In general i would start to assemble a couple of floating elements type breakwater marina and get the business going keeping an eye on being modular and expandable, sparse connection between floating elements will favor aquaculture.
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I have no doubth that you can grow and harvest a whole eco sistem below and around a seastead. The most critical phase is the start up phase where you have only money for a few small cages, no lab, limited knowledge and need something simple to start and make money - what would your recommendation for that kind of start up be?
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