Hi guys...
Just a couple of things that I would add and comment on. Coral Banded will only be aggressive to others of their kind from all accounts I have read. They will go after other shrimp if there is a space problem or fighting over food. Most smart shrimp will keep away from them and most shrimp are faster. These guys move a little slow so they should be able to manuver away should an attack come. I had one in my 125 along with 8 other shrimps of various species with no attacks or deaths due to the Coral Banded.
The feeding is correct, meaty or
shrimp pellets kept mine happy. They also will rummage through the rocks for worms and such, as well as the sand. Dr Ron doesn't recommend them in keeping a DSB since they will do this, but I am not positive that they are that destructive to a DSB. I simply have not had enough experience or read enough about it.
Arrow crabs are very aggressive to others

Have to watch them, they will also munch on all your good bristle worms.
Now to the Iodine question. I have read alot of posts that say that Iodine is poison to Inverts and that while some is always present as a base element or trace amounts, dosing it as an additive could be leathel. The molting is due to the irritation to the shrimp. I think Doug made a comment once he dosed Iodine in order to encourage molt in order to reduce his Camel Backs that he couldn't catch

So....... I wouldn't worry about adding it. That is just my opinion though from what I have read here and other places. I'm sure one of the more experienced folks can add or detract that.