Replacing agar-agar with gelatin I'm not able to purchase agar-agar (yet), so is there a rule for replacing the quantity? I've seen a recipe with 0,5 spoon of agar-agar for 1 spoon of gelatin. Is that the usual proportion?

Additional: is there a difference in treatment to activate the agar-agar or gelatin?
"Texture" the hydrocolloid recipe collection says the typical concentration of agar agar is:


0.2% will set
0.5% gives firm jelly


How much gelatin you need depends on the bloom (strength) of your gelatin.
Page 82 tells you how to convert measurements from one bloom strength to another.