I got my 240g (LeeMar, glass, euro braced with LeeMar stand and hood, light, sump, skimmer, pumps, sand, RO
unit, 250lbs live rock, 3 fish, etc for $1000 on Craigslist). I added some Hydor Koralia powerheads for more flow.
I agree with looking over the LFS
one and offering less. The worst they can say is NO, but I bet they'd like to get rid of it.
Look over CL
and see what is in your area that is used and you will get an idea of costs. You want a skimmer that can handle 2x your water volume. For fish-only, lights don't matter much. Sump just needs to hold the skimmer unless you want to have a refugium. You will want a good return pump, as the plumbing from the sump will likely be lengthy with corner overflows/returns. Prices can vary wildly, but I would guess $150-300 for lights, $200-400 skimmer, $150-250 return pump, sump=depends how you go, maybe $250-350 for additional powerheads, heaters are additional too if you need them.
Keep in mind the cost of water changes and salt. That adds up over time too.
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