Well, after several suggestions to add some dithers to my grammode tank, I did. I have a 3.5" male grammode in a 55, alone. I added 6, 2" Buenos Aires tetras yesterday afternoon. I thought they would give him some competition and stimulate feeding and I thought they were big enough to not resemble food. The lfs owner that sold them to me said they were fast and should be okay. I have one left today, and that one has a conspicuous chunk taken out of his belly and he is fading fast. The rest disappeared or were found dead, systematically one by one, once they were put in the tank. Right before the lights went out last night there were 4, very scared tetras still there. Today at noon when the lights came on, one mortally wounded tetra left.
When I introduced them I acclimated them like I do most fish and they were schooling pretty well and eating within 15 minutes after release. I put in a bunch of fake plants to give them some hiding spaces and break up line-of-sight attack lanes. He came out and was checking them out soon and I left them after feeding him a piece of freeze-dried krill. I came back a few hours later and one was dead and another missing. The tetras were not schooling anymore and he seemed to have each one hemmed-up in a corner of the tank. The grammode seemed to know what he was doing, but I'm not sure. He would go check on each one and make sure the fish was still in its corner. I sat and watched for awhile and figured I'd let the chips fall where they may. Lesson learned. I think I'm gonna ditch the dither idea. I don't have access to any convicts over an inch and I don't think the small ones would do well. Maybe larger dithers like full-grown giant danios may work.
When I introduced them I acclimated them like I do most fish and they were schooling pretty well and eating within 15 minutes after release. I put in a bunch of fake plants to give them some hiding spaces and break up line-of-sight attack lanes. He came out and was checking them out soon and I left them after feeding him a piece of freeze-dried krill. I came back a few hours later and one was dead and another missing. The tetras were not schooling anymore and he seemed to have each one hemmed-up in a corner of the tank. The grammode seemed to know what he was doing, but I'm not sure. He would go check on each one and make sure the fish was still in its corner. I sat and watched for awhile and figured I'd let the chips fall where they may. Lesson learned. I think I'm gonna ditch the dither idea. I don't have access to any convicts over an inch and I don't think the small ones would do well. Maybe larger dithers like full-grown giant danios may work.