Harlequin rasbora behavior - get more

[Maggie]

I started out in early November with 8 rasboras in a 45 gallon tank. Unfortunately,  one got stuck in equipment and died, down to 7. Their behavior was odd to me, always sort of skittish, nearly always avoided the lower half of the aquarium (24" deep) except at water change time when stressed. I got 12 more rasboras in December and added them from quarantine yesterday.

First off, everyone's behavior instantly changed. The newcomers were literally welcomed to the group before the last fish was out of the net. I can tell they're more at ease, and they're exploring parts where I've never seen them, like the lower left corner, in front of the ever-growing sword. The younger 6 (so cute - half the size of the adults) from the new group are having a blast playing around the bubbles from the sponge filter. Its adorable to see younger and older together, like a big family with varying levels of energy and excitement.  And I haven't seen the adult males aggressively going after each other so much like before!

To anyone considering these fish, I suggest to keep them in as large, and especially as long, of a tank as possible, and more than 7 or 8 fish if you have room. They are much more relaxed when there are more of them.

It took me 7 hours yesterday to move them, break down the quarantine tank, sterilize all the equipment, clean the floors, and do the fish towel laundry. I am so glad to have that all done! There's nothing like waking up today, with no heavy chores that I absolutely must do, and knowing my fish also appear to think it was all well worth it.

 

[Shmaty]

I love these fish. When they are happiest, their entire body(minus the black obviously) glows a rich copper red and their eyes are like fire!

In my experience they definetely like larger groups. Id say double digits should be a minimum. Anything less and they wont show face. They tend to take a back seat if larger fish are present. Give them live plants( ideally dense stem plants) and they'll start making babies. Dont be surprised if the young take a long time to join the more boisterous adults. Mine absolutely go gaga for crushed up meal worms. They dont care whats near by once these hut the water. That being said, they arent picky eaters. They'll eat pretty much anything. They do tend to stay glued to the upper sections of the aquarium. They also like to have dense foliage near the surface or in a corner. I dont often see them in the foliage, unless spawning, but they linger near by it. I've also played around with low and high flow and them dont seem to care either way.

I love these guys. Definetely recommend them if you want a bunch of fish swimming around in a group. I dont think i'd call them schooling but I would say they are shoaling, for sure.

[Maggie]

@Shmaty one of my stem plants is only about 6" from the surface and several more are on the way up. I don't know the name if this one but it's interesting to see how the top leaves differ from the lower. 

[Colu]

Bigger the group the better