As hashy said you wont need nutes for a little while and definitely get soom root enhancement products.
I use biobizz light mix and I believe it to be similar to FF. I didnt use nute for the first 10 days. Then I gave a very light feed to see how they took it, personally I thought I overfed, but I didnt, it helped massively and they were bushy little monsters in no time! Good choice on the soil btw, if i could get FF i would have done.
Hope this helps