I was wondering: what if a planet (such as earth) suddenly had all surface tension removed (mainly in water, because all carbon based life forms need it.). What would happen?
Surface tension is caused by the mutual attraction between molecules (mostly Van der Waals forces) of a liquid. These forces are way bigger than the gravitational attractions between the same molecules involved.
If the surface tension is gone, it means that there is no longer attraction between molecules, and with this you bid farewell to any liquid, which will starts behaving as a gas, expanding until it occupies all the volume at its disposal.
Therefore good bye oceans, lakes, blood and even cellular content. In a short sentence: good bye life.