Hey Shael,
Oh no what a bummer! I wonder what happened…I just looked up what would affect agar in setting up; I saw at https://foodarazzi.com/?p=1402 that foods that are too acidic (like kiwi) and other foods (like peaches) have enzymes that break down the gelling ability.
One theory could be that since you heated it for longer, it needed more than 5 minutes to cool before being poured over the tart?
Also, I used pear juice for the nectar. It’s possible that the extra apple juice was too acidic.
That website also mentions differences in strength depending on when the agar is harvested.
Finally, I used agar powder, not agar flakes. Since both are listed as options, it seems like that shouldn’t matter but maybe if you use flakes you require a larger quantity.
Thanks for the update, and good luck!
Christine

Whoops, I meant 1 and 1/4 cups of apple juice! (1/4 cup to replace the fruit nectar)
.-= Shael´s last blog ..Shael DiscoKitty added a new photo to the album. =-.