Large tank design.

Well it's not a Reef tank so lighting wouldn't be critical.

I'm guessing around 8k to start it off, and a few hundred a month in maint costs? I currently don't WC my tank and it has no ill effects, FOWLR.

This is within the next 2 years, as when I move it will be built into the house between the living room/kitchen. Better start planning now than to rush right..especially with a costly build.

I thought it would make a unique tank setup..but if it's not realistically feasible over say just a 150 gallon LONG tank for refugium..

After thinking it's a little silly to put a tank just for the return pump and heater and reactors..so just put them in with the skimmer.

 

I didn't say it can't be done. It can very easily be done if you have the financial stability to do so. I am simply recommending that this be priced out and make sure that your ducks are in a row before committing to such a financial responsibility. Unexpected "things" arise in life...

 

If its a basement build, have a typical sump under the tank you can use for a frag set up that overflows to basement. If you are running an internal model skimmer, put the skimmer in this sump for easy maintenance. If you want to run an external skimmer then have the overflow go directly to that protein skimmer and then dumps into the fuge system.

For the fuges you could do 3 44 or 55 gallon brutes on a stair step so each is about 6" lower than the last and can gravity drain to the next.

1.) With socks and covered - no rock if you are actually worried about detritus (I hate socks and on a large build strongly discourage there use, too much work for no real benefit - if you don't go the sock route then make the 2 fuge twice. 2/3rock chaeto on top) You will want to take any auto w/c from here deposit fresh w/c water in return section.

2.) Next brute filled 2/3 with rock then chaeto on top.

3.) And the last as a cryptic fuge with just live rock and no light for sponges to grow.

From there have it overflow into a typical sump tank. With baffles to stop bubbles and all reactors / dosing before being returned up.

This will give you up to 150 gallons of fuge for about $300 (including wood for stand) and give you a running ton of room for biological filtration. (This is basically modeled after Randy Holmes Farley's set up)