oneeyeluke said:Nitrogen-based fertiliser, is not needed with new soil. If you use it you will cause the plant to produce more foliage than tomatoes. The extra nitrogen causes a very dark green color to the leaves and weakens the plant and help bugs and disease to attack the plants.
Nitrogen does two things to the pH when it comes in contact with the soil. Ammonium Nitrogen will drop the pH like a rock and Nitrate Nitrogen will raise it to a alkaline range. So the problem you have is caused from the introduction of Nitrogen when it wasn't needed.