for soil, the three pack of nutes will probably last you for almost 2 grows if your following the instructions, but probably not all the way through your second grow. im in themiddle of my second grow and im running out of big bloom. the only reason why is because i use big bloom throughout my grow from veg to harvest. its a catalyst for your nutrients. this is why they recommend using tigerbloom with your bigbloom during flower. the big bloom is merely a catalyst for whatever bloom nute your gonna use. the tiger bloom is the actual blooming nutrient.
The FF line is an awesome line to use, and its hard to burn your plants with, unless your intentiionally trying to fuck your shit up. Since your using Open Ses right now, you should go pick up Tiger n big as soon as you can, and start using them. You really should have been using them before you started using the powder nutes, but its not like its gonna hurt anything to do it your own way. If you need the feeding schedule for FF nutrients, either go to the FF website :
www.foxfarm.com , or get yourself a General Hydroponics catalogue. theyre awesome, and youll probably come up with a couple new ideas to add on to your grow once you look through the whole damn thing, lol.
good luck with your grow man. how bout some pics of what your baby looks like right now??