The People I talk to always say have it set at 68 degrees in the winter time
No, as long as whatever is in the freezer is frozen, your good.
minus eighteen celsius
Ideally a domestic freezer should be a minimum of -18 centigrade.
at least -18 degrees
Zero
-18
-18 degrees
I keep my temp. between 75-80 for my 2 year old..
Do you mean "why does water freeze into globs in the freezer?" If not, you probably either need a new freezer, or you need to make the temp. in the freezer lower so they dont melt.Most freezers have either a knob that you can turn on/in them or instructions in a manual on how to change the temp.
Fish are cold blooded, but need to be adjusted to the temp of the water. Slowly if its hot water being adjusted them you need to slowly rise the temp of the water to the temp of the water out side and the opposite for lowering the temp by the way this is all wrong so please don't read that.
It all depends on the temp
Refrigerators should be set at 40°F maximum.
The answer is no whether you mean Fahrenheit or Centigrade.