Neon tetra isolating itself from school?

Good evening everyone! I am new to the hobby and just started my very first fish tank this week after wanting to try the hobby for a long time! It is a fully cycled 55 gallon aquarium. Right now there are 15 neon tetras in the tank I purchased 4 days ago. One neon in particular has been isolating itself from the others recently. This particular fish floats in one corner of the tank toward the bottom and will remain there for quite long periods of time. The other 14 neons are quite active schoolers but this fish rarely schools unless it is feeding time or on other rare occasions. There has been some aggression going on in the tank, presumably the tetra establishing their pecking order. I am not sure if this fish was bullied causing social isolation or if I should be worried about disease. As aforementioned, since I am new to the hobby I do not own another tank to create a quarantine tank. I am stuck between taking the fish out and euthanizing it to be safe from neon tetra disease or waiting it out and seeing what happens. Below is a picture. I should also add the ammonia and nitrite is 0 and nitrate is about 20. Thank you in advance.

 

Good evening everyone! I am new to the hobby and just started my very first fish tank this week after wanting to try the hobby for a long time! It is a fully cycled 55 gallon aquarium. Right now there are 15 neon tetras in the tank I purchased 4 days ago. One neon in particular has been isolating itself from the others recently. This particular fish floats in one corner of the tank toward the bottom and will remain there for quite long periods of time. The other 14 neons are quite active schoolers but this fish rarely schools unless it is feeding time or on other rare occasions. There has been some aggression going on in the tank, presumably the tetra establishing their pecking order. I am not sure if this fish was bullied causing social isolation or if I should be worried about disease. As aforementioned, since I am new to the hobby I do not own another tank to create a quarantine tank. I am stuck between taking the fish out and euthanizing it to be safe from neon tetra disease or waiting it out and seeing what happens. Below is a picture. I should also add the ammonia and nitrite is 0 and nitrate is about 20. Thank you in advance.

Does it have any thing on its body ?, ich or injury?

 

Does it have any thing on its body ?, ich or injury?

Hi there,

Granted I am an untrained eye, I do not see anything incredibly obvious that appears to ich or injury.

 

Given you have no QT tank, I'd remove the fish and euthanize it. I know that sounds harsh, but I typically lean toward caution with this sort of thing.

 

Given you have no QT tank, I'd remove the fish and euthanize it.

Extreme much?

 

Extreme much?

Perhaps. And, I hesitated sharing my thoughts. But, this "extreme" approach has served me well over the years. I just think it's often best to remove a stressed/possibly sick fish in an effort to protect the remaining healthy fish in the tank.

 

Perhaps. And, I hesitated sharing my thoughts. But, this "extreme" approach has served me well over the years. I just think it's often best to remove a stressed/possibly sick fish in an effort to protect the remaining healthy fish in the tank.

Yes I agree with separating euthanizing it might be premature when it could be saved

 

Thanks for the thoughts all. I will be monitoring the situation and I think if the behavior doesn’t clear by the end of the weekend or if anything gets worse I will remove and euthanize the fish.

 

You could add a few more neons. He might be healthy but just ostracized from the group & a larger school might help that. I had an ember tetra do the same thing, but it's healthy and now rejoins the group at times. I could be wrong, though.

 

Thanks for the input. That’s what is tricky about this, it could very well be social isolation due to bullying, which I would hate to remove and euthanize a fish for. On the flip side of that however, I am also hesitant to add more fish right now since there is the possibility of disease.

 

You say the tank is a week old, and cycled???

I have had neon's for the last 45 years, and although they are not like they use to be.

I would not take him out and euthanize him.

I would give him a few more days to settle into his new home first.

I have 25 neon's in a 125 with other fish and I have (1) neon that loves to be alone most of the time, and he's been in the tank 1-1/2 years.

P.S. call me crazy but in just over 45 years with many tanks at the same time, I've never had a QT tank. And I have never lost a fish to any type of disease.

 

You say the tank is a week old, and cycled???

I have had neon's for the last 45 years, and although they are not like they use to be.

I would not take him out and euthanize him.

I would give him a few more days to settle into his new home first.

I have 25 neon's in a 125 with other fish and I have (1) neon that loves to be alone most of the time, and he's been in the tank 1-1/2 years.

P.S. call me crazy but in just over 45 years with many tanks at the same time, I've never had a QT tank. And I have never lost a fish to any type of disease.

Thanks for the response. I did a fishless cycle with ammonia which took about 36 days and then yes, these neons have been in the tank for about 5 days now. Thanks for the words of encouragement. It’s nice to know it might not be something to worry about.

 

P.S. call me crazy but in just over 45 years with many tanks at the same time, I've never had a QT tank. And I have never lost a fish to any type of disease.

Wow. That's an amazing track record.

I've been keeping aquariums for over 30 years...most of that time without a QT tank either. But, unlike you, I have certainly lost some fishes to disease along the way.

 

Very common for neons to exclude the sick ones when you get them. Usually that sick one will die and and another one will get sick and shunned from the group and so on. Might be outdated but I always understood these neon "diseases" to be transmitted through contact so as they chase the sick ones the others get infected.

Anyways, happened to my school as well but I managed to get the "loners" to fully recover (in pH 7.8 hard water) by doing this:
Large tank, low density (75g with about ~12 neons).
Densely planted so lots of line-of-sight blockers.
Little to zero light goes past the surface due to the high plant density.
Little to no feeding and frequent large water changes ~30-50% (all food are sinking pellets as they will be too scared to go to the surface initially).

 

I'd say there is a white spot in the tailbase.
I can't recall which disease is causing this but I have seen this more often.