Fox farms ferts are some of the most complete ferts on the market. If you are not going to add anything to your watering mixture, I would recommend fox farms.
However if money is an issue you can mix your own ferts for much less cost.
Normal miracle grow all purpose plant food has an npk of 24-8-16,
If you add a little epsom salt for magnesium and sulfer
Also adding a little bonemeal will add to the low P in the miracle grow fertilizer and will also add many micro nutrients.
You can also buy micro nutrient ferts at any garden center.
You could purchase all of this and add it as you feel necessary, for less than the fox farms products, but keep in mind that you need to respond to what your plant is telling you, give it what it needs and it will return the favor with increased yields.
No matter what ferts you decide on, the first couple of weeks dilute the mixture to 1/2 strength.
For example, the miracle grow instructions will say for potted plants use a 1/2 tsp fert/gallon of water. The first time you feed your babies this mixture should be more like 1/4 tsp/gallon. By the time you start flowering you can slowly up your fertilizer strength to about 3/4 tsp/gallon.
Your plants will definitely reward your patients and care