Killer Guppy

  1. KaluOwe

    KaluOwe Valued Member Member

    I've got a male guppy who's killing my neon tetras, we have 5 females with him for him to focus on and he only seems interested in bothering the tetras and trying to mate with a swordtail. Any ideas on the problem?
     
  2. fjh

    fjh Well Known Member Member

    1. What's your entire stock in the tank?
    2. What size is the tank is how much decor do you have? (A picture would be great)

    It is unusual for a guppy to attack a school of neon tetras. Are you sure the tetras aren't sick and therefore easy targets or just dying on their own? If you are positive the male guppy is killing them, I would separate him in a breeder net or his own tank for the time being and let the remaining tetras recover.
     
  3. OP
    OP
    KaluOwe

    KaluOwe Valued Member Member

    IMG_20170802_232311737.jpg I'll put this in list format, but for starters, this is a 40-gallon long tank with 2 Penguin 350b filters, one with a set of bio-wheels. In the tank there are:
    • Swordtails. 2 female, 1 male.
    • Yoyo loach: 2.
    • Corydora catfish: 4
    • Guppies: 5 female, 1 male.
    • Platy: 1 female.
    • Molly: 1 female.
    • White Cloud Minnow: 1
    • Neon tetra: 4
    • Golden Shiner Minnow: 1
    Please note that I do not have any control of what goes into the tank, my dad buys what he wants and I clean up the mess :(
     
  4. fjh

    fjh Well Known Member Member

    Darn, I'm sorry about your dad. I also feel bad for your fish, like those poor minnows :/

    Anyway nothing too blatant in your stock and a 40g should be plenty of space for the tetra. One thing I see in your picture though is that there's a lot of open space, and only one piece of decor can actually reach the water surface. Breaking the killer guppy's line of sight is a major factor in reducing his aggression. Would it be possible to put let's say a tall piece of driftwood between the glass vase and the plant? And add some floating moss (or similar)? I know most people like to have few decorations in their tank so that they can see their fish, but fewer hiding places can stress the fish and, such as now, can lead to increased aggression. I guess it would be like not having any walls in your house - try taking a shower or working in peace. Could you do it? Well yes. Is it better to have the walls? Yes also.

    Apart from that, sorry I'm not much help. There isn't any perfect explanation as to why the guppy is agressive, and only toward the tetra. I still think it more likely the tetra were already ill, especially if your dad just randomly adds things to the tank.