First off. Don't add anything just yet. When and if you do, use something that is balanced. Its the only way to move forward until you can read those leaves like a book.
You say you were watering with well water?
Well water can be high in iron. Do have access to the last water test?
And flushing is just going to make it worse. You'll water log the rootzone, cause the ph to dive, and leach out your mobile nutes. (I'm trying to get away from the hydo "thinking" but this seems to be the direction were going so...)
When ph'ing the water, are you accounting for the elements? Example - its easy to go over with K and too much potassium will lockout cal, mag, zinc, and iron.
How did you determine the soils ph? Slurry or run-off?
If I look at just the pics? Its presenting K def.
Wish I could be more helpful