In my 180 lts tank one of the little cories is really ill (has bad wounds dont know who attaced him)and just about hanging on. As i dont have a hospital tank at the moment I put him in a little floating breeding trap because the other fish were begining to attack him. In the tank there are 4 male blue gouramis which have been really aggressive towards the little fella. Yesterday i noticed that my betta was hanging around the breeding trap. I was worried that he was also being agressive but as the other fish came up to the trap my betta flared at them and chased them away!!!! Its as if he is protecting the cory even if my betta is on the other side of the tank and sees a fish near the trap he darts over to rescue the little cory. Its so sweet to watch just got to hope that he recovers.