As far as I know they all mix with water, regardless of where you buy them or the brand. I would just follow the directions. But be sure to get something that approximates the Fox Farm formula. You can probably get their nute ratios online at their website. Just jot them down and take the formula to your local garden store, or head shop and tell them you're looking for nutes with those specs. Also, you could send off for them by mail. Don't know what that would cost. But I hear Canadian nutes are good too. If it's your first grow, it's going to be a test run no matter what you use. Just stay close to the Fox Farm ratios and you should be okay.