When I restarted my tank I had a cal. level of less than 20ppm, so Purple up was a feasable solution to regenerate the advancement. I added nothing except the purpleup directly to the tank once a week for 2 months then checked my level and was reading over 500ppm, so I stopped. After waiting another 3 weeks my cal. level was down to 460ppm..
Yes it boosted the systems coraline growth and now I only keep level with b-ionic.
Purple up is fine to add directly to the tank, but as stated drop it in front of a PH or it's not going to mix very well. Your tank will turn a funky shade of hazy purple for a few hours as well, so don't let it bother you too much.
The final question is, Do you really need Purpleup? I ask because it doesn't give you coraline it only basically helps with what coraline needs to grow and really will not benifit much else.
This is how the tank will look after a dosing of purpleup. Note the hazy purple coloring