The only way to get more loot is if you run it on normal then on hard. The chests you only get once no matter what, though there is the chest right before the gorgans maze that sometimes gives out twice. Bosses will drop twice (oracles, templer, gatekeeper, and atheon) if you run normal then hard, like stated above. If you run it on hard first you will get double drops from bosses (rewards for hard and normal). No rewards then for running it in normal. If you have multiple characters you can run it again with same parameters. Other then that the raid only gives out once a week. If you are able to run it on hard, rumors are that you have a better chance of getting better loot from bosses as you are pulling twice out of a better pool of prizes (if you didn't know, there are certain raid weapons and armor (ie helmet from atheon) you can only get on hard).

Can run the normal raid and hard raid once a week for loot or just run the hard level raid once a week which merges the rewards from both the normal and hard rewards won't gain any rewards until weekly reset on tuesdays

2 times on each character. 1 time hard 1 time normal. But if you do hard first Then normal Then u won't recieve loot on normal.