I have a list of deficiencies and toxicity from my hydroponic store, im trying to scan it but my scanner is all muffed up...i read it over and looked for anything about spotting and heres what i found,

CALCIUM
Deficiency: Young leaves are affected first and become small and distorted or chlorotic with irregular margins, spotting or necrotic areas. Bud development is inhibited and root may be under developed or die back. Fruit may be stunted or deformed.
Toxicity: Difficult to distinguish visually. May precipitate with sulfur in solution and cause clouding or residual in tank.


BORON
Deficiency: Stem and root meristems often die. Root tips often become swollen and discolored. Internal tissues may rot and become host to fungal disease. Leaves show various symptoms which include drying, thickening, distorting, wilting, and chlorotic or necrotic spotting.
Toxicity: Yellowing of leaf tip followed by necrosis of the leave beginning at tips or margins and progressing inward. Some plants are especially sensitive to boron accumulation.

COPPER
Deficiency: Young leave may become dark green and twisted. The may die back or just exhibit necrotic spots. Growth and yield will be deficient as well.
Toxicity: Reduced growth followed by symptoms of iron chlorosis, stunting, reduced branching, abnormal darkening and thickening of roots. This element is essential but extremely toxic in excess.

I am unclear if it is any of these deficiencies but i hope itll help you out a little bit..im going to fix my scanner and if upon anyones request i will post the informative paper on here. Sorry if it doesn't spring any clues!