I always mix perlite into my soil mix no matter what kind im using. I mix it somewhere around 2 parts soil 1 part perlite. Also i use the whole Fox Farm Line Liquids and Solubles, I love the stuff. When Im feeding mine for the first 3 weeks I give them FoxFarm BigBloom @ 2 TBL/Gal til about week 3-4. After that I switch to GrowBig: Start out mixing the liquid @ about 1/3 strength (1TSP/Gal) for the first 1-2 feedings, then step it up to half strength (1.5-2 TSP/Gal) for the 3-5 feedings, then after that I mix my solution
@ full strength or a little under like (2.5 TSP/Gal) for the rest of the Vegitative schedule unitl the lights are turned back to 12/12. Remember per my FoxFarm feeding schedule in weeks 3&4 of flowering you give your plants a shot of GrowBig @ 2 TSP/Gal to help get them the needed nitrogen they need to flower. I recommend getting FF TigerBloom &
FF BigBloom also if you dont have them, they work great or at least they do for me. And if money is not an issue Id also advise getting there soluble line up (FF OpenSesame, BeastieBloomz, ChaChing) they also work great, you mix them inconjunction with the liquids. The solubles run around $93-$103 for the three depending on what hydro stores you buy them from, on the internet you can get the 3 cheaper. I think on amazon.com you can get the tri pack for around $75 w/ S&H and on Ebay.com the tri pack is around $83 w/ S&H. That just my two cents on the conversation, hopefully this helps.
*Disclaimer* All statements made above are purely fictional and hypothetically what I may do were I in that situation.