Remove air bubbles from open casting mold

I know some general solutions for this problem , but I am not familiar with your cast.
1. You can heat to the bowl of resin.
2. You should reduce surface tension of resin.By adding a solvent or by adding a defoamer such as silicone liquids.The best result achieved by adding the thinnest (and consequently the cheapeest)silicone liquid .
3. You should pour the resin in bowl, slowly and you can tilt the bowl during addition the resin.

Use a vacuum. Place your container in a vacuum chamber (decicator) and evacuate it.
Regards,

Peter P

My best experians is to use a vibration system underneath the mold during the filling of the mold.

Spray a mist of rubbing alcohol over the rising air bubbles. This will causes them to burst, leaving the pour surface relatively smooth.