Hi I'm in need of a little help i live in the UK so measuring sizes are different to the us and im no good at at math haha could some one help me get around what magnesium products-chemicals I need and how many grams to use per us gallon of water my tank is 200ltr im new to this i have been reading on the web but can't get my head around it is kalkwasser 1part or 2 part I think I read that kalkwassers diy magnesium mix is different to the other part mix I don't want to get anything wrong and mess things up