Help - I may have to name one Hannibal Lector

[thedeanorama]

I don't want to cross post but I have a bit of an issue with some new Cardinals purchased yesterday.

The background on whats going on is here ([Only Registered Users Can See Links.]) and also here ([Only Registered Users Can See Links.])

The questions I have at this stage I guess are 2 fold:

A) what do I do with No.7?
B) are nipped fins something that require treatment with a fin rot medication?

The rest of the group dynamic was as expected yesterday and this morning, though they seem a little stressed right now - staying a bit separated and near the bottom of the tank (I would be too if I had been hunted for the past 12 hours). I just hope that this doesn't push any of the others over the edge as well.

[Justy]

I have anti-social tetra #7 isolated in a net floating in the tank. The remaining tetras seem calmer. None of them are showing the anti-social behaviour that #7 was showing, no chasing or nipping, so I have to assume that I have isolated the right fish. Now to decide what to do with it since we don't have another cycled tank to move him to and I wouldn't want to subject another school of tetras to his treatment.

I can now see that the dorsal fin on one of the remaining tetras is looking really bad, it is completely white, very ragged, and looks like part of its back was nipped as well. Do these grow back or will it become the delayed victim as well?

There is another tetra with a white nipped dorsal fin who has been hiding; I haven't seen it since before I isolated #7. The tank is fairly heavily planted, which the other tetras seem to like, but it makes it hard to find the missing ones.

The tetra with a slightly nipped tail seems to be doing just fine and schooling with the 2 non-victimized tetras.

[Justy]

I can now see that the dorsal fin on one of the remaining tetras is looking really bad, it is completely white, very ragged, and looks like part of its back was nipped as well. Do these grow back or will it become the delayed victim as well?
I think I know the answer to this one... The poor guy is trying to swim with the other 3 but sometimes gets caught in the current and spun around. I saw him flipped over and over and around, it took him quite a while to stabilize. If he can live till the fins grow back a bit he'll probably be fine but I'm not certain he will. I saw him 'laying on the piece of wood in the tank looking very limp. He did eventually recover but his ability to stabilize himself is very much compromised.

I'm not sure what I'm going to say to our son, we had 6 fish when he left for school and now we have 5 with 1 of them in a time out. The 6th is still MIA, which is odd since he didn't seem to be doing that badly earlier today.

[WoadCelt]

Heya!
I'm sorry to hear that you ended up losing #7. Given the date of your post I'm not sure if any of this well help - but I'll just relay the experiences I've had with my neons.

At one point I had problems with a really, really aggressive neon tetra who liked bullying, nipping and biting all the others. The aggression was solved by isolating it in a breeding net box within the main tank for ten days and then reintroducing it. As the others had rebuilt their social structure in its absence it returned as an 'outsider' and there was a marked behavioural change - it reintegrated fully but was a lot more placid and social.

I've found that the addition of Melafix and Pimafix to the main tank has markedly helped heal the odd fin tear and bite. If it is really bad sometimes isolating the affected fish can help so it can rest and recover. Giving a mild saline solution bath to the individually affected fish may also help.

[Lady Hobbs]

Fins will grow back once established and with good clean water. Not unusual to see some fraying on fish that have been shipped a long distance as these have been.

These fish are small and they also can't fight a strong current. I keep my wee guys in a 29 gallon with a Cascade 300 filter. I like this filter for the little ones because it adjusts from 0 to all the way high. I only run it to break the waters surface. It may not be the most rated filter out there but is a great filter if you want one that has adjustable flow rates.

I would put your secluded guy back in the tank. All fish have a leader and he may be trying to find his place in the crowd. More of them will hold down what aggression he has, as well.

I have no idea what happened to those that died just as I have no explanation for my 6 out of 12 neons that just died for me. I didn't think they looked too great when I bought them, frankly, but it was a chance I took. Only one died outright. The others were pulled from the tank when they began to flounder and I knew they were about to die.

[thedeanorama]

The 4 remaining fish seem to be doing okay now. There is a white speck/dot where the I think I have too much current for them (see most recent journal post) as they sit as far out of the current as possible.

When I go online to find out what the optimum conditions are for a Cardinal I get mixed results. ph reported at one source should be 4-6, others say 6-7.5. Since I'm at roughly 6.6 I'm good based on one source, but too high based on another. According to all sources my temp is fine (steady 80F).

We released the prisoner into the general population on Friday night and seems to be settled now. They mostly school (not that 4 is a school) but there is one thats a little more nervous than the rest and hides more.

Some of this could be my lighting as well as I've yet to introduce any surface plants for my 4watts/gallon. I'll have to query the plant forum I think.