did you ever find a cal/nit with less N?
You can get 13-0-0 calcium nitrate instead of the 15-0-0 jacks uses. You can get it in 14-0-0, 15.5-0-0, and 17-0-0 as well. There is also Biomin Calcium 1-0-0 which is an organic product for soil. Comes in a liquid.
I've thought of using 11-0-0 magnesium nitrate 9% Mg instead of calcium nitrate and using Calcium EDTA chelated 9.7% to replace the calcium but that doesn't make much sense unless you really want to lower the nitrogen level. I try and keep things simple and swapping this and adding that just complicates things There are a ton of different combinations that will all perform well.
Biomin® Calcium, 1-0-0
OMRI LISTED. Boost Calcium and Nitrogen Levels With This Chelated Soil Amendment
"BIOMIN CALCIUM contains amino acid complexed calcium designed for soil and foliar application. It is completely bioavailable and non-phytotoxic to plants when applied in accordance to directions. Designed to prevent and correct micronutrient deficiency and to boost crops during critical or fast growing periods. May be applied with nitrogen fertilizer. GUARANTEED ANALYSIS Calcium (Ca)..........................................5.0%
5.0% Complexed Calcium Derived from calcium amino acid complex."
I've been using this 13-0-0 for years. You can get the same thing online just in a different branded package. It all comes from the same factories. Jacks doesn't make calcium nitrate they just repackage it.