What kind of rainbow is this?

[Freddie]

Hi, a few weeks ago I was at my lfs & saw 4 young rainbowfish. Id read about them & this was the first time id ever seen any for sale. So I thought most rainbows only get 3-4", but ive recently learned they can get bigger. Im not sure wat kind they are since their label was mostly rubbed out. My questions are, what kind, how big, & they are being kept in a 55 gal with 2 angels, 1 RS, & 1 peacock eel, so id also like 2 knw wether theyre fine where they are or if they should be moved 2 another tank. Any helpd b greatly appreciated thanks.

 

[Wroberson]

It looks like an Australian Rainbow Fish. Male.

A 55 gallon is a good size for the fish. They do best in long tanks and in small groups of 4-5. The sexes should be balanced. I say male because the rear fin is long and nearly touches the tail. Females will have short fins. A general rule for all rainbow fish are the males tend to have brighter colors and a distinct hump that makes the head and mouth look like a beak. Some females also have a shorter hump, but the mouth and nose do not resemble beaks.

 

[Freddie]

It looks like an Australian Rainbow Fish. Male.

A 55 gallon is a good size for the fish. They do best in long tanks and in small groups of 4-5. The sexes should be balanced. I say male because the rear fin is long and nearly touches the tail. Females will have short fins. A general rule for all rainbow fish are the males tend to have brighter colors and a distinct hump that makes the head and mouth look like a beak. Some females also have a shorter hump, but the mouth and nose do not resemble beaks.

Then the other 3 will b females, thanks for the info!

 

[Botanica]

My brother has a school of Australian Rainbowfish in his 220 gallon tank and they are full grown at 5+ inches... Surprised me when I saw them as they were only 2 inches when I last saw them in May.

 

[Freddie]

Wow, I guess that gives me something 2 look forward to

 

[Wroberson]

The rear fins are definitely easy to notice the difference.
You might even notice pointed fins on males and curved fins on the females.
I'm obviously having difficulty describing the fins.
But I know the difference when I see it.
They get a decent size of 4-5 inches if you like bigger fish.

If you see any fish display, another way you can tell males from female is the color changes from the nose up to the hump. I don't remember seeing anything flashy with Australian rainbows, but the other rainbows all change colors with a stripe from nose to hump.