Appearently there are two different factions in Iceland.
There is an Arabic faction of muslims in Iceland which fasts for 22hours!
The Turkish community in Iceland is a little less strict and have their iftar at around 9pm so they "only" fast for about 18hours.
you are livign in muslim country, so actually the majority of ppl fast and there is a good "ambiance" for ppl who fast, most my familly go back to algeria during the month of ramadan even if its more hot than here (just for u know, here in France is from 3h48 to 21h58, so actually 18h? with temperature between 25 to 30°C) so i can tell u being in country where all ppl also fast, etc like that make it more easy, than in other country where its not the same culture/custom.