Good soil nutrients

I just started 30 plants in sunshine #4 mix and was wondering what are some good soil nutes that won't break the bank. I haven't grown inside on soil in years so any help is much appreciated.

I'm going to transplant these into 5 gallon containers and give them a 45 day veg before i flip the lights to flower. They are at day 20 now.

C19

View attachment 22322

View attachment 22323