boilies are just some type of experiment.
you have to play with boilies (try to take every bolie you have and try them all at least ones.
Also try to use the spodrocket 5 times at the same spot and try to trow your tackle the closest to where the spod rocket hit the water.
Also experiment with ground bait mixes (you can put more bags in one recipe slot.)
Today i was fishing in the czech lake and i got 7, 17kg carps.
my opinion is that the czech lake is better if you want medium/big carps and if you want more money and xp