Topic: Evil fish

[dustbowl_debutante]

So my demasoni are killing one another off.  I'm down to 3 of them now.  I think I was told by my local "fish dude" (local breeder from whom I buy my fish) that they are notorious for showing aggression against their own kind, but they had all lived together peacefully for 3 months before they started this behavior.  He told me that I needed a group of at least 6 to prevent this, so I added 3 per week until I had 9.  I thought that perhaps I didn't have enough hiding places in the tank, so last night, after cleaning the tank and netting two more dead demasoni bodies, I sat down and actually counted the caves.  There are a minimum of 2 caves per fish (I only counted the ones I could actually see - there are more within the rock piles that I can't see.).

Why all of this sudden aggression only with the one species?  Could it be that since I got them as babies, the aggression is simply a sign that they are hitting adulthood?

How do I stop this aggression?  Or should I just let it take it's course and then replace them with a different species altogether?  What do you guys think?

And as always, thank you all.

[Maddy mad man]

Is their spawning activity within the group leading to aggression against other tankmates?

[johnl]

Spawning will greatly increase aggression. The only way I know of to stop either is to separate the fish.

[Vern]

Why all of this sudden aggression only with the one species?

Demasoni are highly aggressive, especially to their own kind. The dominant male will take out his rivals quickly before starting on the females. Also he won't take very well to other species which have a similar colouration.

Could it be that since I got them as babies, the aggression is simply a sign that they are hitting adulthood?

It sounds like a classic hierarchical battle and yes, it's an aging process. Your Alpha male is simply claiming his territory.

How do I stop this aggression?  Or should I just let it take it's course and then replace them with a different species altogether?  What do you guys think?

How big is your tank?  I've know 4 to live ok in a 400 litre but that is rare.  If you don't have the right conditions I'd take them back to your LFS.  Nature taking it's course is likely to leave you with one dominant male fish.  He's right in that if you keep 15 or so in the right environment (i.e. a breeding colony) then they can live together harmoniously but this depends on maintaining a ratio of roughly 10:1 females to males and allowing enough room for the Alpha male to be avoided.  As Demasoni are very difficult to sex this is not always an easy process.  There are also few tank mates you can keep him with.  You'd be best avoiding basically anything with bars or with any blue colouring.

[dustbowl_debutante]

okay, looks like I have some questions to answer...

Vern, it is a 50 gallon tank.  Tankmates are 2 adult yellow labs, 2 juvenile (1 or 1.5 inch) yellow labs, and 2 "mystery fish" (I am thinking they are either cobalt zebras or the blue variety of socolofi - either way, I'm looking to offload them).  There has been abhappy personely no aggression towards any of the other fish in the tank.  Sadly, on Friday, after I posted my question, I went home and found yet another demasoni body laying in the sand...so now I'm down to two. 

And regarding the references to "spawning behavior", I'm assuming that this explains all of the vibrating/shaking they were all doing right before the killing spree began?

I think I'm just giving up on this one...  I'm assuming that my killer, whichever of the two it may be, will eventually get to the one remaining demasoni and then he will stop?  Given his record thusfar, I reckon I will return home from work today to the last dead body    I can't take them to my LPS, since 1) I didn't get them there and 2) I wouldn't wish that on any fish (man, you have never seen such nasty tanks - but that's a whole different rant).  I could perhaps talk the local breeder, from whom I purchased them, into taking them back, but I'm not totally sure.  If I'm down to just one this evening when I get home, can I keep just the one?  Or do I have to have a group of them?

Maybe I could trade the remaining demasoni and the mystery fish back to the local breeder for something a little more friendly.  Anybody know of something I can keep with yellows in a 50 gallon?

[Maddy mad man]

shaking and vibrating =- spawning behaviour as you say and is the likely instigating factor of the seril killings.

Do either of the two left look to have eggs?

What to keep with yellows - something of similar size and temperament like a cobalt blue, or nothing but good decor if breeding is your intention

[dustbowl_debutante]

Well, there is now only one demasoni left standing.  I'm thinking about keeping him and naming him Connor MacLeod...since he decided to go all "Highlander" and everything ("There can only be one.").  Although, my son thought that "Uno" was a good name, too.  Lol.

shaking and vibrating =- spawning behaviour as you say and is the likely instigating factor of the seril killings.

Do either of the two left look to have eggs?

What to keep with yellows - something of similar size and temperament like a cobalt blue, or nothing but good decor if breeding is your intention

Sadly, no eggs...

I would love to breed the yellows...  Can I accomplish this with just the one tank or will babies have to be separated from parents?  How many adult yellows should I stock the tank with?  And I was told that sex can be determined by the amount of black on the fins? Males = more and darker black...  Is this true?  I have 2 adult yellows right now, and two juveniles.  Adult #1 is gorgeous, has very dark black stripe and very dark black on the pelvic fins.  Adult #2 is not quite as large,a bit more timid, black stripe on dorsal fin is not as dark (though still black), with almost transparent black on pelvic fins (can barely even see it at all).  The two juveniles don't have their black markings yet, although the larger of the two is beginning to get the stripe on the dorsal fin a bit...

And I forgot to mention before (probably because they always hide), but I have 2 itty-bitty juvenile synodontis petricola in this tank as well...  So, in total, there are the 4 yellows, 2 blue mystery fish, the lone demasoni and 2 syno petricola in the 50 gallon.  I'm going to need another tank if I'm going to breed the yellows, aren't I?   

[mrbigfish]

Sorry for your losses, but as most of us know Africans can be just as agresssive as CA/SA cichlids. The best intentions and planning often sour just because fish are fish and have their individual tempermant and tolerance for one another. As you say they can get along fine for months and then bang one becomes dominant. I have fouind that the more rocks, caves, and logs I add along with fish the less the agression. Seems like the dominant fish doesn't know who to go after and because of his size can't fit into the smaller spaces. good luck you'll figure it out.

[Maddy mad man]

Lose the demasoni - no choic and give the yellows a species tank with lots of hidey holes.

The only true way to sex a lab.caureleus (yellow) is to vent or observe one holding eggs. 

I uase to seperate the mum or milk her after 2 wks holding - either way i gave her a couple of days in a tank withouit competition for food so she could catch up on food.

Venting and miking/stripping I am happy to explain if reqd.

NB:  I opted for my les favoured word of milking as being the heartthrob here whenever I say stripping the boys get reminded and jealous of my looks and intellect plus witicisms.

[dustbowl_debutante]

Looks like I will have to start looking for another tank (YAY!  I love a good excuse for a new tank!   

How big does the new tank need to be?  My book at home says that yellows can be kept in a tank as small as 25 gallons.  So does this mean I can put them in a 30 or 40 gallon tank and they will breed? 

Lose the demasoni - no choic and give the yellows a species tank with lots of hidey holes.

The only true way to sex a lab.caureleus (yellow) is to vent or observe one holding eggs. 

I uase to seperate the mum or milk her after 2 wks holding - either way i gave her a couple of days in a tank withouit competition for food so she could catch up on food.

Venting and miking/stripping I am happy to explain if reqd.

NB:  I opted for my les favoured word of milking as being the heartthrob here whenever I say stripping the boys get reminded and jealous of my looks and intellect plus witicisms.

Maddy, I have read the posts on venting and milking.  Only problem is that I'm terrified I will hurt/kill one of them if I try to handle them, but I will give it a shot      Now, let me make sure I have this all straight.  Once I notice one who is holding eggs, I wait two weeks, then milk her.  At that point, I put mom into a separate tank so she can catch up on her missed meals.  So, do I put the babies into the species tank, or into the tank with mom, or into their own tank?  Didn't I also read somewhere that mom has to have her own tank as soon as it is evident that she is holding so that food can be withheld?  someting about if she is offered food, she will open her mouth and lose the babies?  Also, what male to female ratio should I have?

Thank you all again, so much!  And I'm sure my fishies thank you too!!!   

[Maddy mad man]

The bigger the M:F ratio the better but sexually mature females people dont part weith too easily and the only sure way is venting.

Most of the time mum wont eat with babies in her mouth.  if you aRE worried about milking then just place her ina  maternity tank and let her spit naTURALLY (about 4wks)

[Vern]

okay, looks like I have some questions to answer...

Vern, it is a 50 gallon tank..... 

Apologies Dustbowl (or should I call you Dusty for short?) I've been dawdling.  Seems to me like you're getting all the info you need from these helpful fellas anyway. 

[dustbowl_debutante]

okay, looks like I have some questions to answer...

Vern, it is a 50 gallon tank..... 

Apologies Dustbowl (or should I call you Dusty for short?) I've been dawdling.  Seems to me like you're getting all the info you need from these helpful fellas anyway. 

LOL.  You guys can shorten my name to anything you like, with perhaps the exception of "Double D".....I think it's giving me a complex.   

And yes, Vern, thank you to you and Maddy and everyone on this one!!!  I think I have enough info to get started, at the very least.  But you know, if and when (the latter being the more likely of the two) I run into trouble or don't know what to do, I'll be back, bugging y'all again!   

You guys are the best!

[Dan]

But you know, if and when (the latter being the more likely of the two) I run into trouble or don't know what to do, I'll be back, bugging y'all again!   

You guys are the best!

  Thats what we are here for.  Any questions you have, please dont hesitate to ask. 

[Maddy mad man]

Double D 

There is a price ... u have to come say hi regularly and perhaps help others even when u dont have a question.