Evil Fish

[mbpted]

I have a black neon tetra that is the oldest fish in my tank - old being relative - I started the tank in April. (about half a year)

It has survived my steep learning curve on how to keep a fish tank: two major fish kill disasters, high ammonia levels and several full water cycles to get the chemistry to a stable and safe level. He's a real trooper.

He is now sharing a 10 gallon tank with 3 skirt tetras, but is definitely the alpha. I've read that black neon tetras are schooling fish so I've been trying to add more to give him some company, but any new black neon I add to the tank dies. I added two more this weekend and within a day, one was gone and the other two days later.

This has been a pattern for the past couple months. I've gone through more than half a dozen new fish (One or two at a time from different stores. In a vain attempt to see if there was a difference in the quality of the fish) and the longest I've been able to keep an extra one around was a week and a half.

My water levels are stable:
pH - 8.2 ppm (a little high for tetras, but I do a very thorough drip acclimation so I don't think this is the problem)
Ammonia - 0 ppm
Nitrites - 0 ppm
Nitrates - 20 ppm

I do a 30-50% water change and vacuum the gravel once a week to keep the tank clean.

This last attempt I watched as closely as I could. At first the three black neons swam around together. This lasted for about an hour or so, and then my original turned on them. Nipping at them while they desperately scurried away. It was more prevalent during feeding time, but not exclusively, he would nip at them whenever they would venture from their hiding places. A real bully. And it was specific. He went for one until it was gone, then turned on the other.

He seems to get along okay with the skirts - which are slightly larger - but he's not afraid to chase them either. For the most part, they leave each other alone. But put another black neon in the tank and this guy gets very territorial. The one that lasted the longest was larger, but that didn't save him in the end.

So what's up with this guy? Is he an anti-social odd ball? (not counting the skirts) Has he been alone for so long that any new black neon is a threat to his space? Is it a gender thing?

And what can I do about it? My plan was to have a small school of skirts and a small school of black neons - then start to introduce some more colorful fish to give the tank some variety, But that strategy's not working. Should I just skip trying to give the black neon some friends and work on a different type of fish?

Any thoughts would be appreciated.

 

[elmo666]

Ok. A couple of things here. Your ph is too high for neons, those newbies aren't acclimatising too well. What decor do you have? Are there any shells, crushed coral or anything else that is calcium based? You could do with getting an accurate reading of your tap water. If that is high then you may have to look at fish more suited to your water. On the subject of bullying, try adding half a dozen black neons at once. Do a large water change the day before and keep an eye on ammonia levels. Adding a group will "dilute" the bullying as, just after introduction is when new fish are most stressed.

 

[Pellet113]

this happened to me too. my opaline gorami, was the first and oldest in the tank, he has this really bad attitude to every one. try adding someone semi-agressive to put him in his place. Thats what worked for me.

 

[Tuxyu3]

try adding someone semi-agressive to put him in his place. Thats what worked for me.

Wouldn't recommend this.

 

[MBOU]

Ph of 8 is fine for Black Neons, thats normal level for a lot of places in the uk, most black neons are tank bred these days anyway, going to be least on the problems.

A black neon left on his own with black skirt tetras is gonig to have to become more aggressive to stand a chance, generally the skirt tetras are bigger and more boistrous so I assume he decided to be the bully rather than the bullied! If he would rather be on his oen and hangs about with the black skirts, i wouldnt stress the tank out by increasing the shoals.

 

[elmo666]

Personally I don't agree with black neons being in a high ph, hard water. They are an acidic, soft water species. Discussing where they may come from , tank bred or not, really isn't relavent as there is simply no way of knowing. If you want them at their best then try and match fish to water conditions that can be maintained. Apart from one individual, you have had no joy with black neons. Just a coincidence? IMO it's not. Switch your stocking to those that like what they're going to be swimming around in. Only then will they be truely happy. Good luck in the future.

 

[Tuxyu3]

Just want to say, how can anybody know if it's a coincidence or not? The simple answer is you can't. You also can't expect most fish keepers to rule out lots of species just because the water isn't ideal, it would be nice for them to be in perfect conditions but it isn't a realistic expectation.

 

[CrustyOnEastCoast]

I have a similar problem ... I have one Pearl Gourami that is a real bully .. chasing everyone around. The existing inhabitants in the tank have learned to cope with it, but anytime I add new fish ... they get stressed to death. I have tried adding various types of different fish and nothing has worked.

I know this doesn't help you in any way, but just sharing that you are not alone.

 

[Questions?]

it is bullying them because tetras are active fish, so they are recomended for a 20 or more gallon tank. he was there first, he thinks it his territory, so he kills the new fish. simple as that. it is likeyou living ina cramped house with three older biosterous siblings, you gett 2 younger siblings, so you pick on them and harass them. try moving them to a bigger tank, then try again. also there is no such thing as an evil fish. they all act the way they were made, and we have to accept that

 

[elmo666]

Just want to say, how can anybody know if it's a coincidence or not? The simple answer is you can't. You also can't expect most fish keepers to rule out lots of species just because the water isn't ideal, it would be nice for them to be in perfect conditions but it isn't a realistic expectation.

The message that this post sends to me is that if you want go keep a certain fish, just do it. That simply isn't right,. Fish have no control over there evironment, relying on us. If your water parameters are way off for a certain species, be responsible and choose something else or adjust your water accordingly. Plenty of people do it. You can't keep discus in anything that isn't soft and below 6.8ph, they deserve the best conditions we can give them and adjusting ph etc is part of that. This goes for "lesser" fish, including tetras.

 

[Tuxyu3]

Just want to say, how can anybody know if it's a coincidence or not? The simple answer is you can't. You also can't expect most fish keepers to rule out lots of species just because the water isn't ideal, it would be nice for them to be in perfect conditions but it isn't a realistic expectation.

The message that this post sends to me is that if you want go keep a certain fish, just do it. That simply isn't right,. Fish have no control over there evironment, relying on us. If your water parameters are way off for a certain species, be responsible and choose something else or adjust your water accordingly. Plenty of people do it. You can't keep discus in anything that isn't soft and below 6.8ph, they deserve the best conditions we can give them and adjusting ph etc is part of that. This goes for "lesser" fish, including tetras.

Im not saying it should be done and to hell with the consequences, just that a fish does not always 'need' the exact conditions it lives in in the wild. Fish don't live in glass tanks in the wild, they don't have a constant temperature, they don't have certain species of plants. These may seem like moronic comparisons but that is my point, where should the line be drawn? If a fish can live in certain conditions and be relatively happy (not talking about this specific case) then do we still need to change? When do the conditions need to change? When they are slightly off? When they are not good enough to breed?

As always i am not trying to start an argument or prove you wrong, i am just trying to show a different aspect for this. I don't believe anyone, not even the most experienced keeper ever, can answer these questions for us. They can give us a good idea and a shove in the right direction but nothing more. It isn't a topic where there is a right and wrong answer, just like the meaning of life, god, life after death and many other things. Hope you see where i am coming from because please be assured i know where you are coming from and i do not think you are wrong either, just that its an impossible question.

 

[elmo666]

The main reason for my post is that an aquarium is never going to mimic conditions in the wild, it is far too small a volume of water and has far more fluctuations. Because of this it is imporant to try and keep our fish healthy. Stress is the single biggest factor in poor fish health. If we can try and get water conditions as close as we can to what we know the fish prefer they will be all the better for this. Ofcourse it isn't always achievable, and I don't take it that your being arguementative at all. Loads of posts on here regarding poor health are mainly down to 2 things: incorrect cycling and ph, normally too high. I just want keepers to make 2 considerations. Firstly, take the time to research a little into what they want to keep. Then make an educated decision as to whether thier tapwater is suited to this. If not, then decide if they're willing to do anything about it. If the answer is yes, happy days, if not, choose something else. You only get out of this hobby what you're willing to put in.

 

[elmo666]

The main reason for my post is that an aquarium is never going to mimic conditions in the wild, it is far too small a volume of water and has far more fluctuations. Because of this it is imporant to try and keep our fish healthy. Stress is the single biggest factor in poor fish health. If we can try and get water conditions as close as we can to what we know the fish prefer they will be all the better for this. Ofcourse it isn't always achievable, and I don't take it that your being arguementative at all. Loads of posts on here regarding poor health are mainly down to 2 things: incorrect cycling and ph, normally too high. I just want keepers to make 2 considerations. Firstly, take the time to research a little into what they want to keep. Then make an educated decision as to whether thier tapwater is suited to this. If not, then decide if they're willing to do anything about it. If the answer is yes, happy days, if not, choose something else. You only get out of this hobby what you're willing to put in.

 

[Questions?]

+1

 

[mbpted]

Thank you all for the responses and discussion.

First I think I should address this:

...also there is no such thing as an evil fish...

I don't really think my fish is "evil" - I was being a bit facetious.

I was trying to find out if this was normal behavior for a fish I had read was a "schooling" fish and preferred others of his kind for company. From the multiple responses, I gather that it is not normal but also not unexpected based on the size of my tank and the company he's been keeping.

I know there are ways to reduce the pH in a tank, but I've been told that it's better to keep a stable level rather than change the existing water conditions. (that's for pH, not Ammonia or Nitrite) However, my efforts have always been to keep the existing fish alive and happy, and I started (or was left) with a black neon and a skirt. I also have limited space so getting a larger tank is not possible at the moment.

I don't want to add a more aggressive fish to the tank to "...put him in his place." as Pellet113 recommended. I think that the skirts are probably agressive enough. And adding 6 more black neons, seems like a lot of fish to add to my tank all at once as elmo666 suggested. I've read that you should add small amounts at a time to not overwhelm the biology and keep the ammonia levels down. Maybe if I had a larger tank, but as I said, that's not possible right now. (any thoughts on this would be appreciated)

I still want to add more fish to my tank, but maybe I should give up on trying to school the black neon, and let him be the loner he's been for so long. (any thoughts on this would be appreciated as well)

After reading the comments above, my thoughts on strategy are heading in this direction:

Separate the black neon into small fish bowl while I acclimate new fish for a few days or a week. Either new black neons, or something that is better suited to the higher pH. Then re-introduce him after the new fish have had a chance to get used to the environment and make it their home. The bowl, alas, is maybe a bit bigger than half a gallon. I use it for acclimating new fish. It certainly would be a limiting environment for the black neon, without carbon filtering or any other amenities, but it would be temporary. Maybe that would "put him in his place." so to speak. The only other place to put him would be in my water changing bucket.

What do you think?