Harlequin rasboras chasing and nipping fins?

Sorry if this isn’t in the right section, I wasn’t entirely sure where to put it! I’ve noticed that my harlequin rasboras have been chasing the other fish in my 30 gallon tank, and they might even be nipping a little my guppy‘s fins look pretty rough, I might have to move him to a quarantine tank or breeder basket of some sort… just now, I was looking at my tank and noticed a harlequin rasbora chasing a blackline rasbora (not sure if that’s the right name for them but that’s what I’m calling it for now lol) and it looked like the harlequin was nipping a bit! Every once in a while they seem to be chasing each other too… how can I prevent this behavior? Do I need to up the school number, or rehome the harlequins so my fish, both existing and future, don’t get terrorized and nipped at? This makes me feel so bad, since I always heard harlequins were supposed to be peaceful…

 

Sometimes more of the aggressive school helps. Works with my serpaes. They too busy nipping each other to go for anyone else.

 

How many do you have?

 

If the Harlequins feel stressed at all, they are prone to nipping just like many other schooling fish. Having a larger number above 8 preferably will help reduce this behavior. As for Harlequins chasing other members of their school, this is completely normal with the fish. However, when feeling confident and comfortable in their tank, they should not be chasing and nipping fins of other species.

If the Harlequin Rasboras do not feel safe in their tank, they are also prone being aggressive. Here are a few questions for you.

As StarGirl said, what is the school size of your Rasboras?

How is the tank setup? (Picture would help in this case)

What is the complete stocking of the tank in question? Other more aggressive tank mates may be stressing them out causing more aggression.

Do you have lots of areas where fish can hide and cover? If the Rasboras can't hide in sufficient spots within the tank, then they are prone to being very stressed and more aggressive as they are towards the bottom of the food chain in the wild.

Do you have lots of live plants in your aquarium? Rasboras love live plants in their tank and makes them more comfortable with their surroundings in their presence, just like in the wild.

I hope we can get to the bottom of what is happening. I love my Rasboras and I am sad it is not working out for you thus far.

 

Sorry it took me a bit to respond, it’s been kind of a busy day… I have 6 harlequins right now, but I’m planning on getting a few more within the next couple months- I just haven’t been able to go down to the LFS for a bit, since I have to consider my parents’ schedules and whether they’re able to drive me. The tank is a 30 gallon (pretty sure long) :
the entire stocking is 6 harlequins, 3 blackline rasboras, and a guppy. I feel bad for not having a full school of blacklines but I got them when I was still a couple months ago and haven’t been able to find them to up the school number. I’m hoping to rehome the guppy soon because he doesn’t fit in very well and I feel like he could be living a better life in a different setup. I have lots and lots of live plants as you can tell from the picture, lol I’m hoping I can fit more in there. I also have some floating plants that the harlequins like to hang out in. The weird thing is, I’ve seen them spawning and trying to lay eggs, so I’m not really sure what the issue is here I hope I can get it fixed soon, because I really love my rasboras.

 

Bump