Tomato Starts Help - I Hope I Didn't Kill Them

Hello,

We began seeing white spots on our 2 month old tomato starts that have been sitting in a cold frame for the last 2 weeks. - first image

After doing some research it seemed like the most likley candidate was some sort of fungal infection.

I decided to use a mix of water, baking soda, potassium bicarbonate, oil, and a drop of dish soap to spary them down - something that I have done in the past to treat powdery mildew.

I might have made it too concentrated - a heaping teaspoon of both baking soda and potassium bicarbonate for a quart of water - As now 12 hours later the leaves of the tomato starts are beggining to turn black on the edges. - second image

Was I wrong to to treat for fungal infection in the first place? Is there something I can do now to help them out?

Thanks!
-Martin

I think you may have gone a bit over board. The baking soda / water spray most likely would have done the trick. Try washing them off. If the white comes back try vinegar and water spray. If you have bunnies make bunny tea for them or a few tablespoons of your used coffee grounds will give them an acid boost.