CleanUp the memory?

[AC Question]

I installed the Secondary ROM in NEXUS 4 and by some cause i had to delete that ROM from my system which i did using MULTIROM manager. Before installing that secondary rom i had 5/12.93 GB of space but now after deleting that ROM my phone has 6.1/12.93 GB. How can i free the space since that ROM was also installed in internal storage and the Residue must remain somewhere over there.
Thank you!

 

[Rukbat]

You had 5GB before, now you have 6.1GB? You gained space, you didn't lose any. (I assume you mean 5GB internal and 12.93GB external/6.1GB internal and 12.93GB external.)