Water volume vs. length vs. width, too much conflicting info...

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FlanBurberry

Black Skirt Tetra
MFK Member
Oct 31, 2015
55
5
13
Millbrook, NY
I have spent at least 2 hours a day for the past few months pouring through info looking for an answer to a question that Ive seen answered a million times but never exactly the question I'm trying to have answered.


I know that the consensus is length > width and from what Ive seen height only adds to the water volume, which in and of itself seems pretty important to me, but length always seems to trump any argument Ive seen.


My local lfs sells 3 larger sized aquariums 120, 125, and 150 gallons. The specs are 60x18x26, 72x18x24, and 48x24x30, respectively.

From all of the info that Ive read, it seems like 6ft. is the answer and thats that, but I just cant seem to wrap my head around that being the best option. I understand the need for terratorial footprint and surface size for O2 exchange, etc. , but I still feel that both the 48" (150) and 60" (120) share some unique advantages.

In the 150 gallon, there is 24" in width which, to me, seems like it would be far superior to the other two, even giving up the extra length. Also, the extra 30 gallons of water volume seem extremely significant (an extra 25% of total water volume than the other tanks). It also seems like, although the extreme height makes it slightly more difficult to reach the bottom for maintenance, it would be much easier (and less equipment) to have a higher circulation of water, because of the reduced footprint.

The 120 gallon seems nearly pointless to me, as you are getting an extra 12" length but reducing 6" of width and losing 30 gallons of water from the 150 gallon. It's also 12" shorter and the same width and water volume as the 125 gallon.

The 125 gallon, from what I've seen, would be most people's clear choice. The 6ft. length allows plenty of swimming space, territorial area, surface area, etc. I definitely see the advantages, especially when it comes to stocking. But, now in order to push the water around sufficiently it will require more power heads and such to make sure that there are no dead zones. Also, being the shortest of the tanks, any driftwood, substrate, etc., needs to be more carefully planned for height, so as not to decrease the swimming area as much, the 18" width would also make that more difficult. But, the fish would have much more room to swim back and forth, even if slightly cramped when turning as an adult.

In my opinion, however flawed, the 150 gallon with a nice extra large piece of driftwood or two across the bottom, with my red O, maybe one other smaller CA cichlid (severum, convict, salvini, etc.) and a rhino pleco (max size 11") would be a perfect setup to me. But, it is the most expensive tank combo, and I definitely want whats best for my O.

My thought is 150g>125g>120g

So in your opinion, what is the best choice and why? If you do decide to answer, please don't just answer longer is better without telling me your thoughts about it, Ive read that a million times already. Also if you could list best to worst choice in order like 1>2>3 that would be super helpful. Thanks for reading and thanks for any thoughts you might share!
bfsDkLK.jpg


(the picture is of the actual tanks in question, I've cropped out the name of the retail store)
 
Well, it always depends on the fish. For an O I'd go with the 125. This is personal opinion I know the O's I've had definitely utilize the length more than the height. For example a 75 or a 90 the added height isn't much of a difference from the ones I've had. Although I think any of the 3 you've posted would be a great tank for an Oscar.

Personally I'd do 125 > 150 > 120 or (Depending on the width of the 120) 125 > 120 = 150.
 
I'd go for the long one on the top right hand side, but I'd maybe consider another manufacturer; I've heard some horror stories about topfin, unless anyone would like to chime in to correct me.

I don't think 4ft tanks are big enough for fish like oscars anymore, the longer tanks with 18" width just feel better
 
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Well, it always depends on the fish. For an O I'd go with the 125. This is personal opinion I know the O's I've had definitely utilize the length more than the height. For example a 75 or a 90 the added height isn't much of a difference from the ones I've had. Although I think any of the 3 you've posted would be a great tank for an Oscar.

Personally I'd do 125 > 150 > 120 or (Depending on the width of the 120) 125 > 120 = 150.

The 120 is the same width as the 125.. 18" and its more expensive and a foot shorter. Thats why I dont think it is even worth considering...
 
So I had the same delima, same tanks as you. I ended up getting the 125's over the 150. Here are some reasons:

1) Foot print. Although the 150 has higher gallonage, the 125 has a bigger foot print. 9 sq ft compared to 8 sq ft.
2) Fish stocked. If you want to have fish that need the 2 ft front to back, you need a tank longer than 4 feed. I feel like a 150 would be a great tank for smaller or more peacefully fish, like discus, but for SA/CA cichlids, the 125 is optimal.
3) Cost. Not the biggest factor but the 125 is cheaper, so even if you consider them the same, why spend more?

In conclusion I'd have to rate as follows 125 > 150 > 120. I know I didn't address the 120 but honestly, I feel like the 125 is far far better. You're getting more or less the same dimensions on the 125 but with an extra foot, so it's better.
 
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The extra 2' in length completely trumps the the extra 6" in width.
You really limit yourself with a 4' tank.
 
Get a 180g, the others will be tight if your oscar hits 14inch.
Out of your suggestion I got the same as blue bear for better viewing and more length for the fish to get some speed up, a plus 1ft fish in 4ft is no good, I have a 100g 4ft and had to house my old 14inch butti in it temporarily and it looked very cramped.
 
I'd go for the long one on the top right hand side, but I'd maybe consider another manufacturer; I've heard some horror stories about topfin, unless anyone would like to chime in to correct me.

I don't think 4ft tanks are big enough for fish like oscars anymore, the longer tanks with 18" width just feel better

I guess the problem with most of the mass produced tanks is that there is going to be a larger percentage of defects by default and we probably hear about the horror stories more often than the success ones, just because of the nature of them being unsatisfactory. I wish that I had more options but there are no lfs near me that carry or even special order tanks over 75 gallons, besides this one :( and I want to get my O out of his 40 breeder asap. Hes only about 4" but he's my favorite fish and I want him to live like a king. I do notice that he utilizes all areas of the tank though, I guess thats why Im concerned about the 18" width on the 125g...
 
Get a 180g, the others will be tight if your oscar hits 14inch.
Out of your suggestion I got the same as blue bear for better viewing and more length for the fish to get some speed up, a plus 1ft fish in 4ft is no good, I have a 100g 4ft and had to house my old 14inch butti in it temporarily and it looked very cramped.

I really wish I could find somewhere that sells 180's but there is nowhere near me and I just cant afford the $200+ just for shipping...
 
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