They look good. Have you been feeding them? The yellowing bottom leaves could be cos they're hungry, the heat could be causing them to use more nutrients, usually a sign of N def but it doesn't look too major to me, for what that's worth cos I'm still pretty inexperienced myself! Although you look to have some brown spots on the yellow leaves so I don't know if that indicates something else going on too. Also noticed the holes in one of the leaves, is that a pest of some kind, caterpillars maybe, or are you just clumsy like me lol? I get that you're wanting to stay organic but if those ferts are the only options you have then I'd go for the tomato food cos I think the others are too out of proportion for veg, but again that's just my thoughts. Overall they look pretty good man, well done