Butterfly in 55 Gallon Tank?

[Aquaraptor]

Hello. I hope I am posting this in the correct area. I have a 55 gallon tank and was hoping to get a klien's butterfly but I'm confused. The other day I went on Liveaquaria and it said that the minimum for a klien's butterfly is 120 gallons. I remember researching klien's butterflies a few months ago, and I thought I remember Liveaquaria having the recommended tank size much smaller for a single butterfly, and 120 gallons if you wanted to keep multiple or with other butterflies. I checked other sources and they all say that a 55 gallon is suitable for one klien's with 120+ being needed for multiple. Is this correct? I thought it was odd that Liveaquaria said the minimum was 120 as it says that the minimum for a kole tang is 70 gallons, but it gets larger than the butterfly, and I thought that the tang would need more swimming room than the butterfly, which adds to why I'm confused (unless there is a different reason Klien's need more room). Can anyone clarify? Thanks in advance for any responses.

[Sniperhank]

Much more than size goes into consideration with saltwater. If la says that size, I'd trust it. They are the most accurate in that department IMO.
For a 55 you should look into the dwarf Angels as you will find them more easily for a 4 ft long tank like a 55.


Sent from my iPhone using Aquarium Advice

[Aquaraptor]

Thank you. As closely related butterfly species are listed on Liveaquaria as being able to live in tanks similar to my size, and I remember Liveaquaria having a different tank size for one klien's and 120 if you wanted multiple, I thought that it was a mistake that they said it needs 120 for one, especially because I could not find any other sources including trusted lfs workers, that said they need a minimum of 120. While I know that there is more to tank size than size of the fish (like how dragonets need large tanks) I thought that for this particular butterfly it was mostly swimming room. Do you know the reason the Klien's butterfly needs a 120 gallon tank? I won't get the fish if it's not suitable for my tank, but I was just curious to what makes them need 120. Thank you

[PB_Smith]

You got me curious so I just looked at all the butterfly fish they have listed and soon it became apparent.
The ones that they say can do fine in a 70 gallon (the smallest recommended) all have a maximum size of ~5" AND/OR they are extremely peaceful and easy to care for.
there are only a few listed that fit the above criteria.

The ones that max out at ~5" and they suggest a 125 or larger is because they are either more aggressive or more difficult to keep.

Every other one gets large and can be more aggressive.

The one you are asking about can get ~6" therefore the larger tank recommendation.

also keep in mind that for tangs and butterflies having a long run to swim is more important than overall capacity.
for example I have an 80 gallon that is 60"x18"x18" which would be better than an 80 gallon that was 48"x20"x20". even though they both have the same approximate capacity.


Length of the tank should always be a consideration when thinking of tangs and butterflies, IMO.

[Aquaraptor]

Thanks for your reply. The Klein's butterfly is listed as both peaceful and easy on Liveaquaria and every other website I have checked, and is recommended as a possible beginner fish do to its hardiness. The pearlscale butterfly, which is less hardy than the Klein's (listed as moderate/intermediate) also grows 6" yet it is recommended for a 70+ on Liveaquaria. The Burgess' butterfly grows 5 1/2 inches (which is fairly close to 6") and is recommended for 70+ on Liveaquaria. The Klein's butterfly is neither aggressive nor difficult to care for, and is no bigger than the pearlscale and close in size to the Burgess', so those reasons are not necessarily why it is listed as 120 gallons+. All the fish listed as 120 minimum are listed as moderate-difficult to keep except for the Klein's.

I know that horizontal swimming space is just as important as volume (and technically a 120 gallon is still four feet long even if it is more than double the volume of a 55 gallon) but I find it weird that that Liveaquaria would recommend 70+ gallons for a 7in kole tang (yes I know that the size of a fish is not the only factor, but we are talking about a tang) that is also moderately difficult to care for, and is semi-aggressive, when I would imagine it would require more horizontal swimming space than the Klein's butterfly.

Whenever I look for stocking information I always check multiple sources and do my best to research the needs of the fish I plan to get. Most of the time I find fairly clear answers, even if there are a few outliers. For instance, a few people say they have kept a yellow tang in a 55 gallon with no problems, but because the vast majority of sources you research and people you ask say a 55 gallon is way too small for a tang, I would not even consider adding one to my tank. In contrast, in my research for the tank size for a Klein's butterfly, the only source I have yet to find that lists more than 50-60+ for a single Klein's is Liveaquaria (not that there aren't other sources somewhere that say otherwise). Normally I would see at least a few other sources that say something larger, whether it be 75+ or higher, but I have not found one. From my understanding a 55 gallon is suitable for a single Klein's butterfly, but as Liveaquaria says different, I am confused.