Ahh good. That's enough room. The Mandarins, as I said above, need to go in last (preferably after a year of the tank running) for there to be enough of a coepod population to support they're feeding. The Sixline Wrasse may complicate this as they feed on pods
with a vengance. So maybe do away with one Mandarin or the Sixline.
I think the Tangs need a late introduction also, and at the same time, so they don't stake out territory in the tank and then attack newcomers to the tank which swim in the territory. Also releasing them at the same time helps prevent fighting, although since these tangs have different body shape and colouration I doubt there will be much, if any fighting between them.
It doesn't really matter when you add the clowns but I recommend that you add them at the same time and if possible, buy the Black Ocellaris and the False Percula's already paired. Also try and release them at opposite ends of the tank so they don't notice eachother, as some fighting might ensue. If you can't buy them paired, get one of each that is noticeably larger than the other, as this will reduce fighting also.