Return to the Aquariums Forum | Post a Follow-Up

Aggressive neon tetras

Posted by uninformed_kitty (My Page) on
Wed, Apr 26, 06 at 12:00

I always have the weirdest pets, and keeping in that tradition, I now have aggressive neon tetras. Out of my little school of five (I was planning to add more when the tank finished cycling), three of them are aggressive to each other and the other two. I know two of them are male, but the third is iffy. None of them will school together for fear of each other, except the two females. Has anyone ever heard of aggressive neons before? This has been going on for a while (a month?), and I was really hoping they'd settle down, but now my small female has no tail fin because someone ate it off. (She still gets around and eats fine, so even if it doesn't grow back, she should have a good life.) I'm planning to give away the aggressive ones as feeder fish later today, unless someone posts a reason why I shouldn't before then. I've currently separated the three into my 2 gallon tank with my female betta, which is my only means of housing them. Obviously, they can't stay like that, which is why I'm taking care of it as soon as possible. So if you have anything to say in their defense, say it now. I would hate to be making a mistake, but this is no longer something I can wait on. The small female has no means of escaping aggressors with her tail the way it is.

Follow-Up Postings:

RE: Aggressive neon tetras

Well, I'm glad I read some more before running off to the fish store with nearly my whole school. My mom looked at my fish last night and said one was having trouble swimming downwards, and I thought that wasn't a big deal because others did it, too, and I thought they just swam with their noses down like that to get a better angle for finding food on the bottom of the tank. But now that my fish are separated, I can clearly see that the two who I thought were fat just from being female are indeed constipated, and I'm afraid it's gone on much too long to cure. I've read somewhere that healthy fish will attack unhealthy fish, which explains the aggressive behavior.

My current plan is to take the two fat ones out of the tank where I can treat them without them being harrassed. I'll starve them for a few days with the exception of one feeding of peas. Unless you think I should feed them regularly with peas in place of fish food. I'm not sure how to go about it exactly, especially about how to prepare the peas. Do I take a frozen pea, thaw it, and then give them the inside bits of it? From what I've read, their insides are already irreparably damaged, but I'd still like to try just in case. I feel horrible about letting them go like this... I had no idea.

RE: Aggressive neon tetras

Its best to fast them for at least 3 days first. Use only peas with no salt etc added. Pop one in a bowl of water and stick it in the microwave for a minute. Let cool and then remove the outside shell. Neons are tiny fish with tiny mouths so chop into the tiniest peices. Feed only a couple peices once every other day.

Its also possible that if they are females, they could be eggbound. Daphnia is a good food to treat with if you are not sure between the two because its high in protein to help the fish pass the eggs, and its high in fiber to releive constipation.

A month or so ago I purchased four more black neons for my own tank. Two died within days of bringing them home and then it was just the most aggressive, largest tetra with the scrawniest, tiniest, most submissive tetra in the quarentine tank. I ended up getting a divider for the QT because of two reasons: 1) the little one was so stressed from harrassment and 2)the big one was so bloated because it ate her food and the little one's food combined. I wasn't totally sure if it was eggs or food, but the divider helped so I could strengthen up the little one and restrict diet for the big one. She wouldn't touch those yucky peas, so I tried feeding a little daphnia every other day. It was a slow progress, but she eventually went back down to normal size and the two live happilly with the others in the main tank now :)

What do you feed them and how much?

RE: Aggressive neon tetras

I feed them once on work days, twice on days off. (I only work two days a week, occasionally three.) Either way, I put food in front of my betta one piece at a time since he's so slow about grabbing food, and then I sprinkle a bit more in once the small fish swim up (which they're learning to do rather quickly). I only give them about as much as they can eat in a minute since I like to watch them eat. That way I'm allowed to feed them again later.

I mainly feed them Tetra BettaMin Tropical Medley, with freeze dried brine shirmp fairly often. I've tossed in a couple freeze dried blood worms before. My betta won't touch them, and I figure it's good to vary their diet anyway. It's hard to get them in small pieces though. Oh, and algae, but they eat that of their own accord, and I don't have much of it at all. Henrietta used to love algae wafers... I thought she was just fat, and I tried to keep food away from her...

But that doesn't matter now since the both of them ended up floating at the top of the tank a bit earlier. First the little one, then the big one, and my other fish started tearing into them. I scooped them out as fast as I could, but they were already so hurt... I euthanized them. I guess the aggression got worse because their conditions got worse... Or vice versa, or both. I really feel horrible when I think about it. It's all my fault. But I'm trying to focus on the fish I do have, and make sure nothing like this happens again.

RE: Aggressive neon tetras

Do the neons eat the Tropical Medly stuff? I've heard a few cases of this causing blockages and bloating in fish. Variety is good, but be careful with freeze dried foods, because they can be dangerous if fed in large amounts. Neons-and most other fish-have stomachs about the size of their eyes, and remember that flakes and other dry foods expand after being wet. I know most food containers say feed for 1-3 minutes or so, but if I did that with my fish I think they'd explode. I crumble enough flakes for them to eat in about 20 seconds 2 times a day. Try letting the F-dried foods soak in a little cup of aquarium water until they are fully expanded, then chop into smaller peices for the fish. I let one of my black neons chew on an algae wafer once and she bit off so much that I could see her abdomen moving in and out! Spirulina flakes are a safer option than algae wafers.

It is also possible that they could have an internal bacterial infection or dropsy, so watch your other fish closely. Were the scales raised on their sides at all?

Sorry thats a lot of information, but I really don't think you did anything wrong. Most people feed their fish about that much and nothing bad happens. I'm sorry you lost your two fish *hug*.

RE: Aggressive neon tetras

Their sides were smooth. I've seen pictures (and real life fish, I think) of goldfish with dropsy, and it wasn't like that. I thought the big one had eggs at first, and when she never laid them, I figured she must just be fat.

I think where I went wrong is for the first few days, I did overfeed my fish. I was trying to get a feel for how much they'd eat.

The freeze dried brine shrimp should be pretty expanded before they get to it. I drop small bits of it in front of my betta, and then the small fish eat the tiny crumbs that fall off my fingers. I'm not really sure about the size of the flakes they eat...

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Aquariums Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here