Here I share with you two similar designs for a "tank" that was used by my teamates. The tank was designed to hold up to a certain volume of a chemical solution and to be slid on an electrovalve. Once the appropriate signal was given from a micro-controller the valve would open and the solution would mix with another one in a glass beaker.
I used some Solidworks equations in both designs in order to constrain some degrees of freedom. The main parameters that must be set by the user are the volume capacity and some "nominal" lengths. I wrote some notes in the equations table in order to remember which variable accounts for which dimension but they are all in greek, so if anyone wants to dig that deep to these parts they have to use some google translate (I apologize for the inconvenience).
Have a nice day.