Aggressive Female Rams

[Super Nova]

Hello all,
I purchased 4 female rams yesterday, as I didn’t want tons of fry I avoided mixing them with males and the females generally looked more vibrant hence my choice, I’m wondering now whether this was a good choice as a day later I see all of them be aggressive towards eachother. They have plenty of hiding spots in the tank and seem to have settled really well. Have I done anything wrong? I was told at my lfs that they were okay as four females being together. Please let me know if this is normal or any help you recommend,
Thank you!

 

[Byron]

First question is, can you be certain they are female? Sexing rams is very difficult in immature fish, and sometimes behaviours are the best guide. Having said that, there is no reason that females cannot be aggressive too; I have certainly seen this when they are spawning/caring for eggs/fry especially. Individual fish temperament can go against the norm. I would need to see the interaction before I would suggest separation or not.

Are these the common or blue ram, or the Bolivian? Not that it matters much.

 

[Super Nova]

First question is, can you be certain they are female? Sexing rams is very difficult in immature fish, and sometimes behaviours are the best guide. Having said that, there is no reason that females cannot be aggressive too; I have certainly seen this when they are spawning/caring for eggs/fry especially. Individual fish temperament can go against the norm. I would need to see the interaction before I would suggest separation or not.

Are these the common or blue ram, or the Bolivian? Not that it matters much.

I think I may have sexed them wrong actually, in the case that they may prehaps all be males should I still be concerned and take any action? I’m not an expert on Rams but I believe mine are the German blue, They are yellow ish with a shine of blue if that helps.

Thank you for the help!

 

[Byron]

I think I may have sexed them wrong actually, in the case that they may prehaps all be males should I still be concerned and take any action? I’m not an expert on Rams but I believe mine are the German blue, They are yellow ish with a shine of blue if that helps.

Thank you for the help!

There are two wild species of Ram in the genus; Mikrogeophagus ramirezi is the common/blue and M. altispinosus is the Bolivian. All of the "varieties" like German blue, gold, etc are derived by selective breeding from M. ramirezi and do not occur wild. Behaviours are the same regardless of variety.

The tank size is not mentioned, so I don't know if I would advise separation assuming these are males. But four males will need at minimum a 4-foot (120 cm) length tank (the volume is not that critical, it is the substrate area for individual territories that is) but there is still the real possibility one will take over and hound the others to eventual death. While breaking up the area with wood, plants, etc can "help," it is not always successful. Individual fish can as always differ from the norm, but generally speaking males will defend "their space" aggressively and this can get more serious the longer they are forced to co-exist in what they see as too confined an area.

In the wild, the hounded fish would simply swim off to another area. Out of sight, out of mind. This is even more impossible to achieve in an aquarium because fish release chemicals called pheromones (read by that species) and allomones (read by other species) and these are present in the water to tell/warn/threaten other fish, so even when "hiding" the fish are still picking up those signals and being stressed. Water changes help to remove some of these substances, but not all and they continue to build up.

My last Bolivian Ram male was in a 5-foot 115g tank with over a hundred characins and cories, and there was not the slightest doubt to me--or the other fish--that the tank space was "his." I found a lovely female that I introduced, before I understood the bonding issue with these fish, and they spawned four times before the male turned on her and killed her. They had not bonded, and even a heavily-planted 5-foot tank did not provide adequate space for her to escape him. We cannot change inherent behaviours programmed into the species' DNA so it is always wise to understand them and provide accordingly.