No, you open a Westpac or ANZ account before you leave for Fiji to use their ATMs because you are still charged 3% of the Australian dollar value as an ‘international transaction fee’. The maximum you can withdraw within 24hrs is $1000 Fijian dollars, so you will pay $20 Australian dollars to access the cash.
As a general rule it is best not to drink water straight from the tap in Fiji to avoid water borne diseases, this includes brushing your teeth with bottled water. Even though officially, in Nadi and Suva and mainland resorts are the safest to drink, it’s best not to have your holiday ruined by avoidable sickness.
Mastercard, Visa and American Express are all accepted as credit cards in Fiji. To avoid the 3-10% international transaction fee on a lot of credit cards, find the best credit cards to take overseas, including Fiji.
No you can not use Aussie dollars in Fiji. The currency in Fiji is the Fijian dollar and is available to buy before you leave (cheapest), at the airport (very expensive) or in Fiji (expensive). Alternatively Fijian money changers will happily change Australian dollars for Fijian dollars for a fee.
The currency best to use in Fiji is the Fijian dollar. Historically it sits around 1.5 Fijian dollars to 1 Australian dollar so $FJ150 will cost you $AU100. There are 5 different Fijian banknotes each with a different colour, they are $5, $10, $20, $50, and $100. In addition there are 6 different coins, they are 5 cents, 10 cents, 20 cents, 50 cents, $1 and $2.
Assuming you pay for your accommodation with a card, for budget travel to Fiji we recommend you bring $300 in cash per week per person. For midrange and luxury travel to Fiji we recommend you bring $500 in cash per week per person. The reason midrange and luxury are the same is that in luxury travel most of your food, drinks and entertainment is charged to your room, which can be paid with a card.