Good replies all, thanks.
I'll look into those threads and links.
Some thoughts:
For me the hobby is as much about tinkering and DIY as it is about the livestock. I find I am pleased but bored with tanks once they are stable so I either wind up with ten tanks (been there) or need a big project I can really sink my teeth into.
After much "negotiation" with the boss, I am consigned to the unheated garage to construct my fishroom - if I ever want one (no I don't park in there
). With that in mind I can either go tropical or coldwater. Tropical in a cool garage = big humidity problems and constant heating, two things I wish to avoid. Plus, I want to eventually run a large system and can't rationalize the extreme cost of LR and store bought corals. So I want to come up with a (relatively) low cost/low tech set up that will consume my ever waking moment
Yes, I plan to stock from the wild.
I've been monitoring the temps in there for a year now and it dips to low 40's in the winter and 60's in the summer. Close enough for a coldwater coastal setup using ambient room temps I hope (no heaters or chillers). This means there will be no condensation issues for the tank in the garage (other than evaporation due to water movement and lights), leaving just the one pane cut through the entryway wall to worry about. I am considering fan tubes running between the studs and venting out the top sill of the cut out.
For the tidal effect I had planned to use a very undersized pump so that it takes a long time to fill up to the high tide drain. Once it hits that mark it can pump for the rest of the cycle like a conventional display/sump set up. I have to think about draining though. It is a good point that I don't want it to backflow too fast or some species may be caught high and dry by accident.
I plan to do more research on species that can handle the slightly warmer overall temps (60 -40F.) but I think tidal zone species fit the bill as their temps are all over the map anyways.
I'll edit this post with a layout of the fishroom design
Here it is. This is one half of our two car garage. I have to build some walls and the tank is shown in two phases. First the 140G. I have now and then a larger plywood tank I plan to build this winter. The empty wall allows for more tanks in the future.
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