For my sulcata 2&1-2yrs eating varied plants zoomed grassland tortoise diet and some carrots and lettuces. For the leopard 8months eating fresh cut grass and other plants and zoomed grassland tortoise diet and greens
When people bring me their turtles and tortoises that they can't keep for whatever reason, they will usually also bring me everything turtle-related that they've had for the animal. Consequently, I have many, many jars of every brand under the sun of calcium powder (plus loads of other stuff). I use it all. I just use up one jar until its gone then grab another, not paying attention to what brand it is. Same goes for the vitamins. Sometimes they give me liquid, sometimes powder. Doesn't matter, I use it all.
I mix up enough chopped greens, weeds and leaves for my babies in a large bowl, enough to last for a couple feedings, and I put about a cap-full of powder into the mixture. For one tortoise I would only use a pinch between my thumb and index finger over that day's offering. I only do this for two feedings a week.