Salt water tanks? What makes it special?

[Gideyon]

I saw advertised a tank that was made for salt water fish.  I've also seen people say they're using a salt water tank (the structure, not the water) for their fresh water fish. 

What makes a salt water tank special for that?   Other than maybe a blue light. I thought the only difference between the two was the water, not the tank themselves. 

Am I missing something or is it just marketing? 

Edited September 2, 2021 by Gideyon

[Jimfish98]

Marketing mostly. Any tank can be used for FW or SW, but of course some set ups lend themselves towards one end of the spectrum better than the other. What I like about those that lend themselves better towards SW is they typically are built with over flows and sumps in mind which are great for hiding filtration and adding volume to the system. I also find since there is a lot of focus on viewing in those set ups, the quality of glass is much higher. 

[Tihshho]

Could you elaborate on what this SW tank was? Years ago they used to advertise tanks as 'Reef Ready' and that mainly just meant a sump. Now you have the all-in-one (AIO) tanks that support a ton of internal and hang-on back attachments that normally freshwater folk won't benefit from. 

[Atitagain]

@Jimfish98makes sense, I always assumed it was marketing as well. But I’ve never had SW and not enough interest to research the fish let alone the tanks. Beautiful everything about them mostly afraid of the $. FW is expensive enough.

[Gideyon]

On 9/2/2021 at 1:54 PM, Tihshho said:

Could you elaborate on what this SW tank was? Years ago they used to advertise tanks as 'Reef Ready' and that mainly just meant a sump. Now you have the all-in-one (AIO) tanks that support a ton of internal and hang-on back attachments that normally freshwater folk won't benefit from. 

Now that you mention it, I think that's what I read re: reef. I can't find it now.    It was one of those ads Facebook shows me because it's looking at my data

[Tihshho]

Gotcha, if it's a standard glass tank and you see a black plastic thing in the corner or middle, that's the overflow system that's been integrated into the tank. Reef ready means the overflow is there, the tank is drilled and some brands come with the bulkhead as well as limited plumbing accessories. For freshwater, sumps are not needed for most setups. Planted tanks are going to have some gain, but if it's not tuned or balanced right a sump might end up causing an issue, especially in high tech setups. The only use in freshwater than benefits from a Reef Ready tank is for larger fish (South American cichlids) or heavily stocked medium/large fish (African cichlids.)

Edited September 2, 2021 by Tihshho

[eatyourpeas]

I am pretty new to SW, but can tell you that the filtration requirements are very different from a planted FW tank. My challenge was also temperature since I am doing a coldwater environment, and a 1" thick glass would have been prohibitively expensive, not to mention heavy, so acrylic was the way to go.

Sumps are great in FW if you are doing large tanks with no vegetation that can absorb the ammonia. Canister filters work just fine for FW, unless you want easy access to the media for cleaning, in which case, you can't beat a sump.