Fish selection for a 7 foot tank vs a 6 foot tank

[CONSPICILLUM]

Surface area to volume isn't nearly the issue it was back in the early days of reefkeeping. Modern reef tanks have access to circulation pumps that render such concerns largely moot. Most tanks, adequately circulated will approach oxygen saturation without large swaths of surface area. The 6 versus 7 foot tank is more about swimming room IME.

As a returning aquarist after a long absence, this is good to know. Surface area was always hammered into me years ago. Thanks.

 

[JaySchulz]

Back to the original question for a moment ....

I keep a few fish in my 265 that I didn't in my prior 180. Hippo tang, Achilles tang and larger anthias that I simply wouldn't have attempted in a 6' foot tank. Trouble is, after living with the 7 footer I wished I'd gone with an 8 footer.

A little off topic but would you have attempted to put those fish in a 6 ft tank if it was a much wider tank? Say 48" wide. I always hear about swimming room and length of tank but do those general guidelines apply with an extra wide tank? Just curious on yours and others opinion.

 

[dread240]

Length, width and aquascaping all factor into that imho. I plan on having very open rock work and would have no second guesses on many of those fish with a 7 x 3 footprint. 7x4 would be even better.

 

[JaySchulz]

Length, width and aquascaping all factor into that imho. I plan on having very open rock work and would have no second guesses on many of those fish with a 7 x 3 footprint. 7x4 would be even better.

Would you feel the same about 6'x4'? The reason I ask is I'm so close to pulling the trigger on a 6'x4'x27". With the spot the tank is going in, I can do

6'x4' or
7'x4' or
6'x6'

I would like to be able to house fish like an Achilles or some of the bigger tangs.

 

[ca1ore]

A little off topic but would you have attempted to put those fish in a 6 ft tank if it was a much wider tank? Say 48" wide. I always hear about swimming room and length of tank but do those general guidelines apply with an extra wide tank? Just curious on yours and others opinion.

Absolutely. Doubling the width would make a huge difference.

 

[ca1ore]

Would you feel the same about 6'x4'? The reason I ask is I'm so close to pulling the trigger on a 6'x4'x27". With the spot the tank is going in, I can do

6'x4' or
7'x4' or
6'x6'

I would like to be able to house fish like an Achilles or some of the bigger tangs.

If you're talking about the 'regular' big tangs like a naso, then yes. For other ones like the unicorn, I think even the tanks you listed are still too small.