Danios aggressive to new fish?

I have 5 zebra danios that I used with a Tetra Safestart cycle...they all came through fine. So today I went out and bought another danio to fill out their school, and also two platies. I posted earlier regarding the platies' attitude towards one another, but I discovered that is the least of my concern...

Almost immediately the danios teamed up (along with their new brother), and started nipping at my male platy...they seemed to focus on his eyes and tail. Anyway, he managed to get away and hide, seemed stressed, but no visible damage done. The female platy has been hiding in an obscure corner of the tank and has managed to avoid the danios thus far.

I know danios are known for being nippy, but it's strange because I figure a school of 6 would keep themselves busy without bothering other fish. Maybe they're just being territorial?

Anyway, I tossed in some plastic floating plants to help break up the territory a little and give the platys some more hiding places...the aggression has lessened a bit since doing that, but the platys are still in hiding (they've only been in the tank a few hours; I'm sure they're just getting used to the new environment.)

Any thoughts or suggestions on how to address this situation?

Update: The male and female platy have managed to stay near each other...not trying to breed or anything, just kind of hovering behind some plants in the bottom back of the tank.

 

How many gallons is the fish tank? If there is not enough water fish may fight so it will not be cramped. That is the only reason I think they would fight. Danios are normally ok with platys

 

Is this your 26 gallons tank? If so, there should be enough room for everyone. Maybe you could try taking everyone out, reorganize your ornaments, then put them back in. This would be like introducing them to new territory.

 

Yeah, my 26g.

The day before I did a revamp of the tank's deco to accommodate a large piece of driftwood I had acquired. I didn't think the danios would establish their territory like that after only a day!

I may give it another day or two and see how the platties are doing...As I type this, it's been about 6 hours since they were introduced to the tank...they're slowly starting to venture out a bit into areas of less cover, but they're still pretty dormant, staying primarily in one spot...the male is starting to pick at some of my plants a bit.

I'd really hate to have to redo the tank, because I have it looking just the way I want it :-\

 

I'd wait, because danios are only nippy when by themselves or in very small groups. It can't be territories, they don't have any....

 

I keep danios and barbs and they do this every time I try to introduce a new species. The barbs will lead the attack and the danios will follow. They don't enjoy tresspassers in the slightest. Recently I added a school of minnows and I placed them in a breeding net for several hours. Once released my fish actually left them alone (one danio did nip a minnow for coming too close to the danio school's favorite spot but no one got hurt).

If your danios aren't attacking the platys anymore, you might not need to arrange everything. Just keep an eye on everybody and see how it goes.

 

These danios are little maniacs! I got them to cycle because they're known as a hardy species, and I actually planned from the beginning to keep them because they're fun to watch...I never thought they would do this.

They seem to have backed off from the platys, but both platys are still kind of hiding out...the male came out to eat a little this morning when I fed the fish, but the female stayed back. They're still kind of hanging together.

 

Danios are mean. I have 5 and the pet store guy said they are "great community fish". They are semI aggressive bullies if you ask me. I'm planning on returning mine for store credit before I let my baby guppies out of their mesh separator.

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Danios are mean. I have 5 and the pet store guy said they are "great community fish". They are semI aggressive bullies if you ask me. I'm planning on returning mine for store credit before I let my baby guppies out of their mesh separator.

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How big is the tank? They are good community fish.....

 

I have a 65 gallon.

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I have a 65 gallon.

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Hmm..... well, sounds like you just got a cranky batch of them...... mine have always been peaceful, unless they are by themselves, then I have issues.....

 

It's been two days since the platies came in...the danios have backed off considerably...occasionally one will go sniff or chase one of the platies for a second or two, but then backs away...it wasn't the ganging-up that I saw when I first brought them in.

I'm planning on adding a few more fish in a couple of weeks once the tank gets a little more established...my plan is to feed the danios as I'm releasing the new fish so the danios are distracted....we'll see how it goes.

 

It's been two days since the platies came in...the danios have backed off considerably...occasionally one will go sniff or chase one of the platies for a second or two, but then backs away...it wasn't the ganging-up that I saw when I first brought them in.

I'm planning on adding a few more fish in a couple of weeks once the tank gets a little more established...my plan is to feed the danios as I'm releasing the new fish so the danios are distracted....we'll see how it goes.

Sounds like a good plan, that always works for me. Good news, too.