simik creature chamber fetal serum wonkiness

[i-make-robots]

There are three fluid inputs on the creature chamber.
For many of the creatures the first input is artificial blood, the second is water or saline, and the third is fetal serum.
Simiks, however, choose the middle pipe for fetal serum.
What gives?

[i-make-robots]

Here's another - only Vessel has two saline inputs. Two! Why?