Car dog bowl

I have just started getting into 3D modelling and haven't got a printer yet to test this out. I came up with this design to allow animals to have drinkable water when traveling in the car.

i left the top off the insert so it can be filled with sand to give it a lower center of gravity when filled with water.

I'd appreciate any and all tips and advice to improve my skills.

If you print it please let me know how you get on.