Please Help Me Understand Tank Size

So right now I'm having to pick between two tanks to upgrade my flowerhorn to. My question is, why do people prefer length so much more over width? Currently he's in a 29g, and I'm deciding between a 40 gallon breeder and a 55. The 29 is basically the same width as a 55g, just longer and taller. But the 40 gallon breeder is longer and wider. Wouldn't it make more sense to have a little more width at the expense of a little height and length? For other tank sizes too, why do people prioritize length over width?

29g: 30 1/4 x 12 1/2 x 18 3/4

40g breeder: 36 3/16 x 18 1/4 x 16 15/16

55g: 48 1/4 x 12 3/4 x 21

See what I mean? No extra width just taller and longer. I get it's more gallons, but wouldn't the fish like a wider tank? Which would you all put him in the 40 gallon breeder or 55g. (I'm growing him out this isn't a permanent situation)

 

Get a 75 gallon lol.

This is why so many people love "breeder" tanks. They are easier to light, and most fish don't need the height. Footprint is preferred unless you have tall fish. If I could have found a 120 breeder I wouldnt have gone with my 180.

 

For small fish, a longer tank means more swimming room back and forth. For larger fish, a wider tank means more space to turn around as they mature. Ideally you get a tank with both so the fish have lots of space, but budgets dictate what is realistic.

 

Like wodesorel said, length is almost always better because it provides more swimming room. Fish like to go back and forth, not round and round. For BIG fish, like your Flowerhorn, you need both. And a Flowerhorn REALLY needs like a 100+ gallon tank. A 125 would be ideal. Dont even bother with a 40 or 55 unless you want to upgrade again in 8 months.

 

Fish swim. I'm of the opinion that they like to swim like kids like to run - the faster they're going the happier they are. So think of a fish tank like a race track. Longer straightaways mean more speed.
Just my opinion.

 

Ok I’ll go with the 55 then. The thing was is that I already have a 40 gallon breeder and a 55g. I don’t have a bigger tank yet but was planning on something like a 120 once he gets a little bigger. Thanks for all your all’s help!

 

Well, I say, if you're getting a 120 eventually, might as well get a 150 lol!....just sayin'...

 

So right now I'm having to pick between two tanks to upgrade my flowerhorn to. My question is, why do people prefer length so much more over width? Currently he's in a 29g, and I'm deciding between a 40 gallon breeder and a 55. The 29 is basically the same width as a 55g, just longer and taller. But the 40 gallon breeder is longer and wider. Wouldn't it make more sense to have a little more width at the expense of a little height and length? For other tank sizes too, why do people prioritize length over width?

29g: 30 1/4 x 12 1/2 x 18 3/4

40g breeder: 36 3/16 x 18 1/4 x 16 15/16

55g: 48 1/4 x 12 3/4 x 21

See what I mean? No extra width just taller and longer. I get it's more gallons, but wouldn't the fish like a wider tank? Which would you all put him in the 40 gallon breeder or 55g. (I'm growing him out this isn't a permanent situation)

I could be wrong but I don't think it is length over width as much as it is better to have both more length and width over more height. I do wish I could upgrade to a 75 from my 55 because the 75 is wider than my 55. You may want to consider getting a 75 instead of a 55 if you can.

 

I have a 55 gallon and only have small fish zebra danios and tetras and they have a lot of swim room. They like to swim in schools. I agree with others that if you have a big fish, then tall is not what you need. Wider and deeper is better. Get the biggest tank you can afford. You won't regret it.

 

I could be wrong but I don't think it is length over width as much as it is better to have both more length and width over more height. I do wish I could upgrade to a 75 from my 55 because the 75 is wider than my 55. You may want to consider getting a 75 instead of a 55 if you can.

I agree, the 75 is the same length but has an extra 6" front to back. It may not seem like a lot but the difference is noticeable when you start to fill a tank with hardscape.