If it really was a misunderstanding, I would simply mail/message one of the mods who banned you. If it was a big shouting match, names called, you selling something as a company, etc... then maybe you should just browse in "read only mode" (which you can do, the banning is simply for posts).
And yeah IP addresses are linked to your actual internet connection, if you have a static one you're screwed (many people have static addresses), if you have a dynamic one, then you can potentially get back on, however they probably banned your user name not your IP address. Unless of course they had a mad spammer who happened to be in a similar block as you so they banned an entire block of IPs.
And there is some use to ReefCentral, I think the DIY section alone is worth it's weight, the "local clubs" of course is simply one huge for sale area so yeah... coral forums seem to be either "Hey look at this new coral I got" or "Lets every one post this species of coral" or "Look an ORA coral that's green... isn't it cool!"

(yeah I unfairly rag on ORA .. I'm sorry

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