Call it what you want my friend, but you have several medium to large fish in an average size tank. Even with your frequent water changes, it's probably difficult for your filtration system to keep up with the bio-load of twice daily feedings. Your RD's problems are certainly attributed to stress. The fact that the symptoms of ich are exacerbated by stress will continue to cause problems for you in this tank. If you have problem children, i.e. the knives, you should separate them from the others. It's great that you're giving your fish a 1000g pond, but in the meantime the problems are going to continue until you start losing fish. If you have any way to do it, separate the fish as best you can until you finish the pond project. Good luck.