Dominant platy harassing one platy in particular

[Katsplaty]

Hi everyone, I have just started keeping fish, I had goldfish as a child and was recommended platy fish when I went to the pet shop.
I picked out a fish I liked (the dominant one) and was told it was a male and if I put a female with it I would have tons of babies (which they would potentially eat) I asked if it would be a problem to have a male tank and she and several other aquarium shop workers told me that they are usually docile.
I bought two male platy fish that day and the dominant one seemed as if he was trying to mate with the smaller fish the next day. He was going sideways and sticking out the gonopodium part.
I was going to return him then they seemed to settle down.
5 days later I bought two more and these two are a similar size to the dominant orange platy.
Now the thing is the dominant one is harassing one fish in particular (blue) he barges and chases him if he goes close to the orange one. He seems to keep trying to swim up. The red one he doesn’t as in the beginning I saw him barge him back (once, I’m not sure if it’s a regular thing) and the littlest one is fine, he often swims lower in the tank.

My tank is 20 litres, I do plan on upgrading at some point but, as I have only had the tank for two weeks or so I don’t want to go that yet.
I have been doing water changes most days. Or every couple of days as I read it was a good idea to get rid of nitrite.

My concern after reading other posts is that fish can die from stress. I don’t see any physical damage and don’t think he does much more than barging but, it upsets me to see it.
I am also quite attached to my fish already...
I would love some ideas. Thanks

 

[Katsplaty]

To update, after doing around a 60% water change today this evening the blue platy is now trying to mate the others, mainly the smallest one. They are all male. The red one barged him a little so he continued with the other smaller fish again. I’m not sure what’s going on

 

[AilyNC]

Do you've plants? Floating plants? Places to hide?

I've only had mixed groups of Platies and never ending fry. The male in my tank is an aggressive brat who plagues the female. I had another adult female that died and I think stress added to it.

 

[Katsplaty]

Do you've plants? Floating plants? Places to hide?

I've only had mixed groups of Platies and never ending fry. The male in my tank is an aggressive brat who plagues the female. I had another adult female that died and I think stress added to it.

Thanks for replying, I have 4 plants (one live) a rock that they can enter and another rock.
It’s really stressful watching it, I’m new again to fish keeping and the shop assistant talked me out of getting a mix for that very reason and I couldn’t bear the thought of them eating them. I also don’t have an overly big tank.. the weird behaviour tonight trying to mate the smaller male is worrying. This is the bullied one trying to do it as well.
I kind think I should’ve got all girls

 

[AdoraBelle Dearheart]

Male only livebearer tanks can work. I have six male guppies together right now without issue. The biggest problem is the tank only being 20 litres/five gallons. That's too small for platies. They can't move without seeing each other, no space to establish territories, no places to hide. They're bound to spar a little, some of that happening is normal while they work out a pecking order, but if the bullied one has no where to hide, then it can get relentless. It's also normal for them to display to each other the way they would a female. They still have a drive to mate, even with no females around.

The trick to a male only tank is to have enough space, first and foremost. Secondly, lots of decor and planting to break up lines of sight and provide hiding spots. If there's mostly open clear space, they can see each other easily, and the chase never stops. But in a five gallon tank, you don't have space to provide swimming room as well as dense cover.

Even with those things, while most will settle and be relatively placid with each other, there will always be the odd male who is too driven and too much of a bully to settle into a male only tank. I once had 34 male guppies growing out in the same tank together, and they were all great together - except for one. He was relentless, would pick a target to harass and wouldn't give up, he was a devil. Remove his target, and he'd just pick a new one. That male would have never worked in a male only tank no matter what, he was just to driven to mate and to compete. He'd only have been happy in a tank with females. Out of the 2-300 guppies I've bred, he was the worst male for that, the majority were fine in same sex grow out tanks, with plenty of planting.

 

[AdoraBelle Dearheart]

Thanks for replying, I have 4 plants (one live) a rock that they can enter and another rock.
It’s really stressful watching it, I’m new again to fish keeping and the shop assistant talked me out of getting a mix for that very reason and I couldn’t bear the thought of them eating them. I also don’t have an overly big tank.. the weird behaviour tonight trying to mate the smaller male is worrying. This is the bullied one trying to do it as well.
I kind think I should’ve got all girls

Plenty of female platies will have already been exposed to a male before you get them, and they can store sperm and keep popping out fry every month for a year or more, even without a male around, so it's good you didn't get females! It only takes a male to jump from the male tank to the female in the farm or at the store, and bam, gravid females. So many people buy females and end up with fry, having no idea that they can store sperm, it's good you didn't!

You definitely don't want to add females to a five gallon tank, you really don't have space for fry. If a larger tank and additional planting doesn't help, you might have to consider returning, exchanging or rehoming the bully male I'm afraid, I'm sorry.

 

[Katsplaty]

Plenty of female platies will have already been exposed to a male before you get them, and they can store sperm and keep popping out fry every month for a year or more, even without a male around, so it's good you didn't get females! It only takes a male to jump from the male tank to the female in the farm or at the store, and bam, gravid females. So many people buy females and end up with fry, having no idea that they can store sperm, it's good you didn't!

You definitely don't want to add females to a five gallon tank, you really don't have space for fry. If a larger tank and additional planting doesn't help, you might have to consider returning, exchanging or rehoming the bully male I'm afraid, I'm sorry.

Thank you very much for your replies and time, I think a bigger tank in the near future is the way to go. I can’t right now and having not had fish since I was a child and even then my Mum did a lot so I didn’t realise how aggressive they could be. I was told by so many people in several shops that they would be fine.
They are lovely fish, very active and sweet. I have plants and two rocks one with a cut out to hide in. Thanks for the advice that I did the right thing having only males.
I knew the space thing with fry would be an issue. It’s good to know that you have male only tanks that are fine

 

[Kelp23]

Hi, I had the same issue. I have male and female platies and still have one male who constantly bullies another male. I ended up removing the bully but the little guy who got picked on still hides constantly . Some fish are just A******s unfortunately.

 

[Lajos_Detari]

Livebearer fish like Guppies, Platies, Mollies, Swordtails are always a problem with too many fry.
If I keep them, I will only keep the males.

Anyway, I prefer other type of fish such as Cichlids, Tetras(Characin), Rasboras(Cyprinid), etc.

Some info about fish species:

Guppies

www.qianhufish.com

 

[Katsplaty]

Hi, I had the same issue. I have male and female platies and still have one male who constantly bullies another male. I ended up removing the bully but the little guy who got picked on still hides constantly . Some fish are just A******s unfortunately.

Lol, that really made me laugh so much...
thanks everyone

I now have a slightly new issue.... I removed the bully for an hour to see if it would help and watched the dynamic and within 15 minutes the blue (bullied one) began barging the red one or attempting to anyway...
I then put the orange one back in. Later on probably about 3-4 hours later I added a live plant on wood, I added one other plant yesterday so now have only live plants... and the red one is now barging the orange one (the origina bully) I’m so confused as they got on well before. What has changed? Was it because I took him out (albeit briefly) or the change of scenery in the tank. I don’t get it. The orange one is now racing to get away and the blue is isn’t being chased as much but, I don’t want a new bully situation. I just want them to all get on.

I have also been doing regular water changes as the tank is new and the pet shop said the water was 0 for nitrate 0- Ammonia and 1 for nitrite. What would you suggest? I don’t know if I need to post in a new thread for the second comment. Thanks

 

[itiwhetu]

Plenty of female platies will have already been exposed to a male before you get them, and they can store sperm and keep popping out fry every month for a year or more, even without a male around, so it's good you didn't get females! It only takes a male to jump from the male tank to the female in the farm or at the store, and bam, gravid females. So many people buy females and end up with fry, having no idea that they can store sperm, it's good you didn't!

You definitely don't want to add females to a five gallon tank, you really don't have space for fry. If a larger tank and additional planting doesn't help, you might have to consider returning, exchanging or rehoming the bully male I'm afraid, I'm sorry.

Is there such a thing as a virgin, guppy, platy or swordtail. It is almost impossible to get one. And I would almost certainly say, any fish bought from a LFS would have seen at least one male.