i don't own any but we had them in the lfs i work at about a month ago, they were very active and ate like crazy. it was a group of four but they sold fairly quick so i didn't really get to assess their behavior as a group
Atabapo IIs, great fish. I do 40 to 50% water changes every week and have never had a problem w/ HITH. I have 3 atabapo IIs, recently lost my wc pair of atabapo Is, great fish.