penguin tetra fighting
 

I had 4 Penguin Tetras for about two weeks and they got along with my other fish fine. Then several days ago, one or two started attacking the others, and I thought maybe their numbers were too few, so I went and got 4 more.

After the 4 were initially added, all 8 started to school and seemed to be happy with each other. However, after about 20 minutes, they've started fighting again, and it looks like it's the same two that were fighting before. They also constantly attack my Siamensis Algae Eater whenever it comes close to them. Maybe because the SAE looks similar to them.

What can I do to curtail this? This is in my 40 gallon. I read that they needed space to swim, then I read that they needed heavily planted tanks... Which is it?

My first initial guess was that it was because of the low numbers, but you added 4 more so now you have 8, and they arent known to fight like guppies are. but every now and then there is that one fish that will try and pick a fight with all the others. so i would recommend that you try and catch that one fish and take him back to the store and switch it out for a new one

Are you sure you have Penguin Tetra and not Dawn Tetra? Penguin Tetra, click on shaded name, are VERY peaceful. While Dawn Tetra, also called Panda Tetras, are VERY aggressive.

Here are some pics http://t3.gstatic.com/images?q=tbn:A...qDhNKqVsMDhe2W http://t1.gstatic.com/images?q=tbn:A...Mmhyv6QewrE0Ar True Penguin http://t0.gstatic.com/images?q=tbn:A...G4rMvA5p1ZI6_G This is the panda

Yes, I am. Their lines extend from the eye all the way across their bodies into the lower rear fin.

I wish my Blue Gourami would give them all a spanking and keep them in line.

Photos of my Penguins -

http://img.photobucket.com/albums/v6...-23-25_363.jpg

Yup, those are false, but both are very peaceful, soo I don't know why your having problems. What other fish are in the tank?

usually with my fish, the fish stop acting as aggressive when i add more cover

False?

Stock list -

Blue Gourami
Granite Marble Angelfish
8-10 Kuhli Loaches (lost count)
Starlight White Beam Bristlenose Pleco L183
4 Otoinculus
4 Apistogramma Trifasciatas
Siamensis Algae Eater
a few surviving Red Cherry Shrimp
One Bamboo Shrimp
Millions of Malaysian Trumpet Snails

And the 8 Penguin Tetras...

Here's a somewhat current photo of my tank. Most of the plants are low plants. The taller plants are at the back. -

http://img.photobucket.com/albums/v6...4-27-06_26.jpg

That could also be the problem, not enough cover to make them feel safe.

I do notice that the majority of the Tetras are hiding in the plant cover but the troublemakers are out in the open.

yeah, I would definitely add more cove rin your tank as right now it looks lightly planted and in my experience most tetras do much much better in moderately - heavily planted tanks, and also are less likely to nip other fish's fins. and when you add more cover they will be more confident and come out in the open most likely