My habs' leaves are beginning to look curly and bubbly at the top. Good healthy color, so I figure they need more calcium as the other chilis look fine and are in the exact same soil/soil addition set ups. I just surface dressed around one with tomato tone to see if that helps, but am looking for a good calcium fertilizer that isn't high in nitrate or other nutrients so I don't end up burning them (tomato tone is low at 4 percent nitrate). Also, isn't there another nutrient they need to help with the uptake of calcium? Is it magnesium? With that in mind, any suggestions?