Doris, I use Jack's Something-or-Other soluble fertilizer, and I also use Spray and Grow, without cocowet, it's a lot of micro things like copper, zinc, boron and others. I feed very very weakly with every watering, unless somebody is really dry, then I use fresh water. Oh, and my mix and watering is on the alkaline side. The Adeniums that are in the ground here do great in soil that is so alkaline that it turns test strips dark blue, not anywhere green. Acid is yellow, and a medium green is neutral on test strips.
SO, an alkaline environment is better for Adeniums. Sometimes I add a little pinch of baking soda to a gallon of water for my plants.
Plus I've spent a lot of money buying Adeniums from Taiwan growers!