Male Guppy Problem

[andy36yr19]

My friend started a 20 gallon freshwater tank. He put 5 male guppies in there. The tank is full to he cant do a 1:3 ratio. 3 guppies died and the 2 are picking at eachother and nipping tails to where they're ripped. Is there a way to stop the aggression? Maybe add more males?

 

[Colin_T]

Check the water quality for ammonia, nitrite, nitrate, pH and GH and post the results (in numbers) here.

Guppies need water with a pH above 7.0 and a general hardness (GH) above 200ppm.

If the tank is newly set up there is probably an ammonia or nitrite issue and doing a 75% water change and gravel cleaning the substrate each day for a week should help.

Guppies should be kept in a single sex tank (males only or females only). However, don't get any more fish until we find out what the problem is. If there is a water quality issue, adding more fish will make it worse. If it's a disease, adding new fish will make them sick.

Post pictures of the fish.

Add lots of plants, especially floating plants like Water Sprite (Ceratopteris thalictroides/ cornuta).

 

[Lunar Jetman]

When you say full, what else is in there?

I wouldn't keep guppies in a single sex tank, or at least not males. They'll chase each other around if there are no females in there. If your mate wanted guppies and can only get 5 in his tank I would get 4 females and 1 male. It is entirely possible they're fighting with each other due to lack of space or just territory. They're not an aggressive species as such but if they're cramped in and are just males, the behaviour you're seeing is more than possible.

 

[Colin_T]

The problem with having male and females together is the males harass and pester the females continuously. So when the females are pregnant and trying to give birth, they have to deal with the males trying to breed with them. It's easier on the females if they don't have to deal with males constantly trying to breed with them.

Having said that, if you want males and females then get at least 6 females per male, preferably more females (10 or more), and then wait for the babies

 

[FishGuest5123]

I have a tank with 7 males along with neon tetras and a few platies. They all do great together. They’ve been living together for about a year now. My tank is a 20 long.

 

[Lunar Jetman]

I have a tank with 7 males along with neon tetras and a few platies. They all do great together. They’ve been living together for about a year now. My tank is a 20 long.

In fairness, that's why I did ask what else was in Andy36y19's tank as knowing that might help explain what is going on.

 

[FishGuest5123]

In fairness, that's why I did ask what else was in Andy36y19's tank as knowing that might help explain what is going on.

In fairness, I wasn’t arguing with you. I was simply stating my own experience and what worked for me. My apologies if it came across as anything else to you.

 

[Lunar Jetman]

In fairness, I wasn’t arguing with you. I was simply stating my own experience and what worked for me. My apologies if it came across as anything else to you.

Nothing to apologise for. We're both trying to assist the OP based on our experiences. I wonder what he means by

The tank is full to he cant do a 1:3 ratio.

as if it really is full, maybe there's too many or too many of the wrong kinds. We won't know until he replies.

 

[FishGuest5123]

Nothing to apologise for. We're both trying to assist the OP based on our experiences. I wonder what he we.means by as if it really is full, maybe there's too many or too many of the wrong kinds. We won't know until he replies.

Yes, very good point! Let’s see.

 

[NickAu]

Any time you add male fish to an established colony of the same species expect trouble, The new fish is an intruder and needs to find its place in the pecking order, I have seen male guppies in a all male guppy tank kill new males, within minutes of being added they started picking at him till there was a huge hole between his head and dorsal fin.