Hi, Painguy,

They are still a tad young for cal/mag, unless your water comes from volcanic soil wells or R/O filters.

In places like Florida with a limestone base, adding cal/mag to tap water is unnecessary and can get toxic.
Your water company sends an analysis once a year.
It will tell you what to expect, but watching your plants closely, will tell you what they want.

You can probably give them a few more weeks before you need to think about cal/mag.
But it does get important when they begin to flower.
It takes very little so don't overdo it.
Less is more.
Love kills!

Aloha,
Weeze