What is the monthly maintenance cost of a large FOWLR tank (1500 gallons & up) ?

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saltypuffer

Feeder Fish
Feb 10, 2025
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Those of you who have massive tanks can you tell me roughly what it costs you monthly to maintain such a large aquarium. I’m looking to potentially build a massive plywood tank down the road for fish only. I’m hopeful that since it’s a FOWLR it will only cost a fraction of what a true Reef tank would.
 
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Everything salty is expensive.

your start up cost will be high, even building your own tank. Price out the biggest protein skimmer and UV you can afford as a starting point.

then figure out your gallonage, lets say you built a 500 gallon- 20% water change will cost about $50 in salt alone.

can't speak to electrical or water as I have solar to support my habits.
 
Everything salty is expensive.

your start up cost will be high, even building your own tank. Price out the biggest protein skimmer and UV you can afford as a starting point.

then figure out your gallonage, lets say you built a 500 gallon- 20% water change will cost about $50 in salt alone.

can't speak to electrical or water as I have solar to support my habits.
I already have a large saltwater reef tank (155 gal total volume) for reference so I’m not as concerned about the equipment costs. I’m just more so wondering if there’s something I’m not thinking of for a FOWLR that I might want to know about. For example I’d definitely need to do more water changes since the bio load will be higher than my reef tank (which I can just dose). It seems very few people have a saltwater tank over 1000G and I’m wondering if there’s a reason for that other than expensive water changes lol.
 
Good luck with it!, my biggest salty is about 120 gallons. FO

I do plan on switching one of my 180's salt for these guys in the next year or so. I'd love a 300gal+

the biggest tanks i encounter are reefs- theres a 600 from MBL aquatics- i don't know if mike is on here. Mr Saltwater has a huge drop off tank, Pollo reef has like a multiple thousand gallon but thats damn near a professional aquarium
 
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The initial cost for sea water mixture for a 1500 gal tank could be @ $500. but
monthy cost would vary.
If a you run an appropriately large protein skimmer , cost might be far less than if you use only standard aquarium filtration, or...
if you run a heavily planted sump/refugium with a plethora of algal types and mangrove trees, that consume nitrate,
you could reduce salt cost, but then again the intense light needed might be a wash.
I use a heaviy planted refugium, with mangrove trees that reduce need forwater changes somewhat, but the refugium sits in a sunlt tropical yard, so no need for expensive artificial lighting.
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