How to keep same particle density after changing radius

[bernardo Joukoski jalowski 0]

Downloaded a CBRN scrypt form the steam workshop. it's size is 50mx50m. i later managed to increase the size of the trigger and the particle area, however, the particles are sparse and can't be seen easily by themselves, they're the only way to know that there is gas in the area.

the scrypt is called "CBRN" by QQ

 

50x50 área (default)

100x100 área (less particles)