Hydrogardens.com
Dry nutrients are the same nutrients- only easier to use, more flexible and STUPID CHEAP compared to the water bottles at the hydro store.
Under no circumstances should you allow anyone to fool you into thinking that pot is a 'special needs' plant that needs shockingly expensive nutrition.
It's a weed. As such, it's really pretty flexible. People have great success with everything from Miracle Grow to Scott's Rose Feed. So why spend more than you have to?