aggressive mollie behavior

[sabrefan117]

I just set up my 10 gallon tank about a week ago. A couple of days ago, I got my first fish for the tank. They included two platys and a dalmatian mollie. The two platys hit if off great and swim everywhere together; however, the mollie tended to stay by himself near the top of the tank.

Thinking he was lonely, I got another dalmation mollie. The new fish will constantly chase and nip at the original mollie. Is this normal behavior? I can't notice any damage to the fish and was thinking it might just be the fish being territorial.

Also, we made sure when we bought the fish that they were all of the same sex (male). We don't want any little fishies swimming around.

What are your thoughts on my mollie's behavior?

 

[sabrefan117]

I should also add that the new mollie doesn't bother the platys all.

 

[Calypso77]

I just set up my 10 gallon tank about a week ago. A couple of days ago, I got my first fish for the tank. They included two platys and a dalmatian mollie. The two platys hit if off great and swim everywhere together; however, the mollie tended to stay by himself near the top of the tank.

Thinking he was lonely, I got another dalmation mollie. The new fish will constantly chase and nip at the original mollie. Is this normal behavior? I can't notice any damage to the fish and was thinking it might just be the fish being territorial.

Also, we made sure when we bought the fish that they were all of the same sex (male). We don't want any little fishies swimming around.

What are your thoughts on my mollie's behavior?

The size of your tank is more then likely the Molly problem you have. They shouldn't be in anything under 20 gals.

 

[BobandBecca]

i am having the same kind of problem with my bolivian rams. i had got my first one (hes about 1 1/2 inches long) a week later got one more (about 2 iches long) from what i had read i thought they would do well together. The first ram 1 1/2" is totally chasing and nipping the larger ram i dont know what to do either.

 

[phishfriend]

Ok first. The tank with Molly's and plat's. you just setup the tank? You need to jump to the AA home page and read "how to start a freshwater aquarium" and learn about "cycling" You tank hasn't been cycled and the info in the article will help you from losing fish.

 

[phishfriend]

i am having the same kind of problem with my bolivian rams. i had got my first one (hes about 1 1/2 inches long) a week later got one more (about 2 iches long) from what i had read i thought they would do well together. The first ram 1 1/2" is totally chasing and nipping the larger ram i dont know what to do either.

I read your thread and saw the pics of your rams(nice). How long has the tank been up?
Ok it's hard to tell but I think you may have two males which means that what your seeing is most like territorial behavior and will
Hopefully die down after awhile! Just keep an eye on them.

 

[Ursi]

What are your water readings?

 

[tamtam]

Your tank is too small for Mollies. They grow to be rather large fish and have a huge bioload as well. 30 gallons is usually the recommended tank size for them.

The aggression is probably combination of things which mostly comes down to their environment. The tank is too small and with so many in there it's over crowded. Both of these will cause stress on fish and can cause aggression. While livebearers are generally peaceful fish there are cases where males will become aggressive with each other. If there isn't enough cover/decor in the tank this will also make things more stressful on them.

In the end you are going to need to return the mollies or upgrade their tank. Aggression rarely goes away on it's own and will get worse as they mature.

Personally I would return the mollies and keep the 2 platys. This is pretty much maxing out your tank in itself. If you are willing or able to upgrade I would get a 30 gallon tank for the mollies and be sure to provide cover and decor, breaking up sight lines also helped curb some aggression.

 

[BobandBecca]

I read your thread and saw the pics of your rams(nice). How long has the tank been up?
Ok it's hard to tell but I think you may have two males which means that what your seeing is most like territorial behavior and will
Hopefully die down after awhile! Just keep an eye on them.

My tank has been set up for about 3 months total. thanks for the help i will see how they get along.

 

[tamtam]

My tank has been set up for about 3 months total. thanks for the help i will see how they get along.

trying changing up your decor. Sometimes when a more aggressive type fish is added to a tank first they will lay claim. Adding another would be seen as taking over it's territory. Move things around so it's "even ground" and be sure to break up sight lines and it should help. Give them areas so that each can claim a space and it should help out.

 

[Freshwater fish guy]

I have two and there aggresive