its just simple bro, your impatient and lookin for a quick fix. You say you were working out a year and reached your potential? BLAH! You can hit 28lbs, within 2 years naturally. Your a rookie and in short this is what i would tell a rookie.
GRAZE LIKE A COW, DONT EAT LIKE A PIG - eat every 2-3 hours, ex. 3 solid meals and 3 shakes. You can workout all you like if your body is depleted of nutrients, you will burn out and all for nothing. I rather miss a workout than a meal.
USE COMPOUND MOVEMENTS - this is where no one can argue this point, if someone does they are liars or out right fools. Use SQUATS, benches, chinups, dips, military presses, DEADLIFTS and bent over rows. Every day i see ectomorphs (skinny) guys doing 20 sets of pec decks and cable cross overs to SHAPE their chests, get real! If your lookin for mass you dont need to do anything else besides whats outlined above.
DRINK WATER - if you tired, you need water, your dehydrated. If your thirsty its already too late. DRINK WATER.
SLEEP - so overlooked and underappreciated, when your tired you take a nap to recover like recharging a battery. Remember you grow OUTSIDE the gym, not inside. When you sleep thats where damaged muscle (from working out) repairs itself. So more rest yields faster results.
juice can wait my friend