Any decent coco has already been buffered. I use Botanicare bricked coco. It's already been flushed/rinsed and buffered. I still rehydrate with a mild nutrient solution of calcium nitrate and a micronutrient blend that has an NPK of 4-10-20. Bricked coco is going to have more dust once rehydrated than bagged coco and many people rinse that out. I use a big tote to rehydrate the 2 kg bricks and then scoop out big handfuls and squeeze out the excess nutrient solution leaving a perfectly moist coco that's ready to use for planting. Most of the really small stuff will end up in the bottom of the tote and gets dumped out back in the garden. So in a way I rinse it.
The good thing about the nutrients you're using is that you'll have plenty of calcium from the calcium nitrate and won't have calcium issues or need to use calmag. You are using the Jack's Professional 5-11-26, calcium nitrate and magnesium sulfate correct? That is pure money in coco and full hydro. You don't need to add anything else to keep your plants nice and happy. Good luck.
however I have 16 seeds with little tap Roots sticking out in paper towel and I'm in a bind for whether I should just get some coco and a cheap bottle of nutrients to hold me over or just go and buy some cheap seedling soil to hold me over until the transplant and then go that route thoughts.
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