Endoamp's main ingredient was Phosphatidylserine which can bought as a bulk powder (more cost effective). I wouldn't exceed 300mgs a day and I find that one dose of 200mgs works well.

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Store it in the fridge. I wouldn't bother capping it, just use digital scales you can buy on amazon.

Not sure if this idea may be useful, (but I'd try it): Geonomyx make a preworkout with Rhodiola Rosea, theanine, Dicaffeine Malate. It's called origin, and the energy is quite smooth and you could just take a half or less serving as a boost when required, just an idea. It's called Origin and doesn't contain Creatine.