Calculator
Reef Tank Cost Calculator
The two questions every new reefer underestimates: what does it cost to build, and what does it cost to run. Here's an honest itemized estimate for both — up-front and monthly.
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Why "how much does a reef tank cost" has no single answer
The tank is the cheap part. Where the money goes is the equipment — lighting, skimmer, flow, and the reverse-osmosis unit you'll need for clean water — and then the ongoing cost of salt, electricity, and test kits. Our estimate splits it out so you can see exactly where each dollar goes and where you can save (buy value gear) versus where you shouldn't (RODI water, a right-sized skimmer).
Up-front vs. monthly
Up-front is a range because you can build the same tank at very different price points — that's the "tier" control. Monthly is mostly electricity (heaters and pumps run 24/7) plus salt and RODI for water changes and a bit for consumables. Bigger tanks cost proportionally more to run; efficient DC gear (the premium tier) actually lowers the monthly bill even as it raises the up-front cost.
These are estimates
Every number here is a reasoned range, not a quote — real prices vary by brand, sales, and where you live. Use it to budget and to sanity-check a build, then pin down the two biggest variable pieces (pump and skimmer) with the exact-sizing calculators linked above.
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