If your going to do barley greens or magnesium--do them apart from meals. Both can buffer acid production and might cause bloating/indigestion. Not a big fan of magnesium supps. They seemed to irritate my gut. I do better with pumpkin seeds which are really high in magnesium. Pumpkin seeds give me better bowel movements than any food. I know Dr. Jeff doesnt recommend seeds or nuts but the pumpkin seeds for me occasionally seem to really help take the edge off/help absorb some of the die off/help with bowels when their sluggish. Pumpkin seeds ive noticed can be a very mild diuretic so i have to supplement with a little sodium in the morning. Potassium i get plenty with food. For some reason Pumpkin seeds are about the only nut+seed that really agrees with me. All the others cause indigestion/bloating. I usually bake them at a low temp to make them more digestible.
Not a big fan of the grassy greens. They made me bloated and constipated. I went overboard with the grasses and realized it was causing more digestive problems than anything. I dont think humans digestive system is designed for a lot of grassy greens. We just dont have the GI tract set up for that. Were designed to eat a lot of variety of foods. Occasionally the grasses might be ok--I would not take them with meals=Buffers too much acid=Bloating and indigestion--been there done that. If you notice in nature dogs/cats will eat grass if they have an upset stomach because it helps to settle an over acidic stomach.
Garden of life is a Good brand for B-vitamins. I wouldnt buy any brand with too many binders/fillers. Tablets can be harder to digest. I would buy garden of life empty the capsule and drink the powder form=easier to digest. Or mix powder form into a mixed drink.