Pearl Danio Aggression or Playing???

[Maltimomma]

I have 3 pearl danio in a 55 gallon tank. I've had them about 6 weeks. They have been very actively swimming together. Yesterday I noticed one in the corner of the tank and when it would try to swim out the largest one would chase it back. Last night the larger one was chasing the third one unmercifully in a tight circle and around the tank. After about 2 hours of this we caught the larger one and put it in the other 55 gallon tank and now all is calm again. My concern was that the one who was being chased would get so stressed it would die. Do you think that may have been mating or just aggression? I really wanted 4 in each tank as they are so pretty and active. Now I don't know if I should do that. The lone danio is now swimming with the rosy barbs.

[blert]

Danios are psychotic, to put it mildly , and their play can get very rambunctious. They really need a proper sized school to spread out the "playfulness". I would up your number to at least five but seven would be better. They are really fun to watch when in a good sized school.

[librarygirl]

Do you know if they are males or females? If you have two males and one female that could be the two males trying to assert dominance and showing off for the female. I have them too but I have 8 (started with 12, 4 died along the way and planning to get a few more). I haven't noticed much aggression with mine, a couple of the males will square off now and then (they swim in a tight circle as you mentioned) but no attacking or injuries. I'd suggest increasing the numbers and try to get more females than males and it should calm down. They are more fun to watch when in a larger group too and it'll help them feel safer.

[Maltimomma]

Originally Posted by librarygirl

Do you know if they are males or females? If you have two males and one female that could be the two males trying to assert dominance and showing off for the female. I have them too but I have 8 (started with 12, 4 died along the way and planning to get a few more). I haven't noticed much aggression with mine, a couple of the males will square off now and then (they swim in a tight circle as you mentioned) but no attacking or injuries. I'd suggest increasing the numbers and try to get more females than males and it should calm down. They are more fun to watch when in a larger group too and it'll help them feel safer.

Thanks for the help. I am willing to increase the number I have, but here's what else I have in the tanks: #1 55 gallon - 5 angels, 2 turquoise rainbows, 2 blue and 1 gold gourami, bn pleco and now just 2 danios. #2 55 gallon - 4 angels, 2 opaline gourami, 4 rosy barbs, 2 bn plecos, and 1 danio. So is it even possible to increase that many danio in either of these tanks? I do really enjoy them and have already ordered 3 more. Any suggestions.

[Maltimomma]

Originally Posted by Maltimomma

Thanks for the help. I am willing to increase the number I have, but here's what else I have in the tanks: #1 55 gallon - 5 angels, 2 turquoise rainbows, 2 blue and 1 gold gourami, bn pleco and now just 2 danios. #2 55 gallon - 4 angels, 2 opaline gourami, 4 rosy barbs, 2 bn plecos, and 1 danio. So is it even possible to increase that many danio in either of these tanks? I do really enjoy them and have already ordered 3 more. Any suggestions.

I don't know what sex they are. I was just thinking maybe I could move the rosy barbs to tank #1 and have 8 danios in #2. What do you think?