Will More Fish Solve Bullying?

[doubledee]

Hi,

I have 5 pencilfish (see sig for proper name!) in my community aquarium. The other day I noticed one of the males had a large swelling on his left hand side and some of the scales were sticking out. I immediately thought it was dropsy. The tank stats are fine. Now I don't think it is dropsy at all and it is down to a physical injury. He has never stopped eating but he's definitely not himself if you know what I mean. The male pencilfish have always chased eachother around but it was all harmless. I've watched them closely and think there are two pairs, although I could be wrong. The other day after a water change I witnessed both pairs spawning, one pairs were spawning for about 2 hours. I have noticed that the injured fish is always hiding in the plants at the top out of the way and the other pencil fish, including the females, chase him and peck at him. Are they having a go at him because he is weakened or because he is the odd one out? I can only presume that the injury was maybe caused by him bashing himself on the bogwood or something. I originally had 6 of them but lost one within a week of adding them to the tank. I'm keeping an eye on the sick fish and have some meds on standby and a small tank setup in another room in just in case but I don't think it is dropsy so the meds I have are probably wrong. As it is, the swelling is going down.

Do you think if I added some more female pencilfish that the bullying would stop or is he just destined to a life of misery in my tank?

 

[doubledee]

Anyone?

 

[Lupin]

Hi,

I have 5 pencilfish (see sig for proper name!) in my community aquarium. The other day I noticed one of the males had a large swelling on his left hand side and some of the scales were sticking out. I immediately thought it was dropsy. The tank stats are fine. Now I don't think it is dropsy at all and it is down to a physical injury. He has never stopped eating but he's definitely not himself if you know what I mean. The male pencilfish have always chased eachother around but it was all harmless. I've watched them closely and think there are two pairs, although I could be wrong. The other day after a water change I witnessed both pairs spawning, one pairs were spawning for about 2 hours. I have noticed that the injured fish is always hiding in the plants at the top out of the way and the other pencil fish, including the females, chase him and peck at him. Are they having a go at him because he is weakened or because he is the odd one out? I can only presume that the injury was maybe caused by him bashing himself on the bogwood or something. I originally had 6 of them but lost one within a week of adding them to the tank. I'm keeping an eye on the sick fish and have some meds on standby and a small tank setup in another room in just in case but I don't think it is dropsy so the meds I have are probably wrong. As it is, the swelling is going down.

Do you think if I added some more female pencilfish that the bullying would stop or is he just destined to a life of misery in my tank?

Any pictures of your pencilfish? While they do spar against each other, they generally do not inflict any damage against another. Fish can peck and inflict harm on weaker ones. It is possible which is why it is recommended you isolate that problematic fish until you sort it out.

 

[doubledee]

Any pictures of your pencilfish? While they do spar against each other, they generally do not inflict any damage against another. Fish can peck and inflict harm on weaker ones. It is possible which is why it is recommended you isolate that problematic fish until you sort it out.

Those photos were taken when I first noticed his lump and thought he had dropsy. The swelling has gone right down now, his side is marked but not badly. He does still get picked on but not nearly as bad. I've seen the males sparring and they don't harm each other but I can only think this poor guy must have bashed himself on the wood etc. whilst trying to get away. Nearly after every water change now, the other four pencilfish spawn in the tank, 1 pair more than the other though.

 

[Tommy Gun]

Do you think if I added some more female pencilfish that the bullying would stop or is he just destined to a life of misery in my tank?

I have to be honest...I have never kept any pencilfish, nor have I read/heard a lot about them. I did notice that most, if not all, of the species profiles I just dug up state that these fish are really rather docile so, even though I don't know a whole lot about them, it sounds as though aggression should be a minimal issue for you. However, it is relatively common for us to come across a fish "acts" or "behaves" in a manner for which the species in general are 'advertised' as being. Perhaps that is what you are experiencing right now and for that reason, I agree Lupin in that, if you can identify which fish is being the 'bully' more so than the others, you could benefit from removing that fish from the tank for a while. This way you will be more able to realize if this is an isolated incident or if it is something you can expect out of all of your fish.

Anyways, to answer your question as to if adding more fish can help with aggression, my answer would be that in many cases, yes it can help to some degree. For example, it is pretty common advice to keep a higher number of Tiger Barbs rather than a few because the 'group setting' seems to make them less apt to be aggressive and/or nip fins. However, while I can't say the reverse is true, in many aspects, the addition of a higher number of fish may not cause them to truly be more docile, but instead, just adds more 'targets' for aggression - hence, the goal is probably more along the lines of hoping any stress or inflicted wounds are 'diluted' as much as possible. In fact, this is the exact same ideology that I employ in my cichlid tank - with the fish being commonly known as adding 'dithers' or 'targets'.

On the other hand though, adding too many dither/target fish to an aquarium which is too small, the benefits of dithers/targets may be void since cramped conditions can actually be a source of aggression in some, if not most cases - meaning there are exceptions, but I don't think your tank and livestock qualify as being.

Additionally, you may be able to help any fish which are low on the 'totem pole' as far as the tank/species' hierarchy by ensuring that the tank is full of places for a bullied fish to quickly escape to no matter where it is currently located...if you haven't already. In fact, even plants (real or fake) can help out greatly in this aspect, while also giving you the ability to reduce 'sight lines' so that one fish cannot see others on the opposite side of the tank.

After noticing the info/stats in your signature, and coupled with your descriptions, I also wonder if another pencilfish is really to blame here. To be honest, even though I completely realize, because I have a few myself, that apistos are looked upon as being 'peaceful' or 'semi-aggressive', this does not mean they are completely risk-free. IMHO and IME we have to be careful when looking at 'labels' such as peaceful or semi-aggressive because these are often relative terms - for example, are your and my apistos as peaceful as community fish, or just peaceful in relation to other cichlids? IMHO, while they are certainly close to the community fish comparison and can be kept with community fish in general, they are probably being labeled as being peaceful versus other cichlids. My point here is that I wonder if your Agassizzi is really the culprit for the wounded pencilfish and you are just seeing the others pick on it because it is injured and at the very bottom of that totem pole I mentioned before. In fact, in quite a few cases, aggression in certain fish is really only apparent during the night time hours when they decide to be more active after a long day of 'hanging out' in their territory - which is exactly the case with my rainbow shark and even a few of my saltwater fish - so you may want to keep an open mind until you can get to the bottom of this problem with a high degree of certainty. Make sense?

For the record, I should point out that many of these 'tricks' for reducing aggression have been and/or typically used for cichlid or other highly aggressive/territorial tanks and not really needed for most community tanks -- however, it sounds as though you may be an exception in this way and of course, IMHO, if these tricks help with cichlids, I cannot see why they won't work for you.

 

[doubledee]

Thanks for the comprehensive reply. I knew adding more fish was recommended for boisterous species like Tiger barbs but wasn't sure if it applied to docile species like pencilfish. I have observed the tank carefully and the only fish that ever bother him are the other pencilfish and more so when they are spawning. He has almost made a full recovery and he has been shoaling again with them but I can't help feeling he is the odd one out. The Apistos are almost certainly not the culprits as the occupy an entirely different level of the tank. The Apistos rarely rise above the bottom levels other than for feeding. They do give the corys a hard time and at this very moment in time, the female is defending a cave I made of stones and pebbles at the front of the tank in the hope that they would spawn in it. They chase the corys, yet they never bother the other inhabitants of the tank other than to 'flare up' and show off their finnage. The tetras are by far a bigger threat to any fry yet they just give them a 'look'! They have spawned before in a tiny hole in my wood at the far left of the tank but I never saw any fry. The female is cleaning the inside of the cave regularly and it is only big enough for her, she is even aggressive at my malaysian trumpet snails who crawl into sight! If I can get hold of some more pencilfish I think I will try at least a couple of females. I think he is the lowest within the heirarchy of the group at the moment and maybe some juveniles might appease that (or move the agression on to one of them. Fish are strange!) for a while. As it is, I'm happy at least that he is no longer sick and will continue to keep an eye on him.

Cheers again for the replies, it's always good to get feedback and bounce ideas around.