you dont need cal mag man....why does everyone think cal mag is a magic solution!!
you will only ever need to use cal mag if using ro water, if your not as youve not said, this is either a ph issue or an enviroment issue.
you should make up a nute solution, let it run for 15mins in the bubbler, then ph it to 5.8
measure ph from inside the bucket and not from the tube.
check room temps etc, bugs etc...your base nutes if using tapwater will have enough cal/mag.
you should be making a solution as above and leaving the buckets for a week, add some benifical microbes and your laughing.
hope this helps!
peace!