wyager:
Are you using an anode resistor? That's crucial. It sounds to me like something's up with your driver IC. Can you post a schematic?
No, what size resistor?
My circuit is as described - no resistors or caps or anything. The nixie plugs into the IC and 180v+, the arduino plugs into the four IC logic pins and the IC is also linked to +5v and GND. All the grounds are linked.