Necrotic Spots on Leaves
I've noticed several necrotic spots on the leaves of some of my tomato seedlings. As the pictures show, the spots start out small and grow larger. The plants are in 1/2 whiskey barrels with potting mix, compost, and Dr. Earth Organic 5 Tomato, Vegetable, & Herb Fertilizer (5-7-3) mixed in per manufacturer's instructions (1/4 cup per 5 gallons of potting mix). I raided them all from seed and put them out a little over a week ago. So far, Brown Berry, Hawaiian Tropic, Black Krim, and Gold Nugget plants have developed this issue. Any ideas as to what this is and the proper course of action to take? Thanks.