Deficiency

Worst thing you can do to a skewed Ph is blindly feed more salts to a plant that is clearly running high ec, the salinity is what will "burn" every tip you have. It's very easy to assume nitrogen but there is no yellow, magnesium is for more likely given a calcium and magnesium can look very similar to nitrogen when it comes to symptoms. Before you do anything get a accurate pH reading of that soil. Until you know anything you is potentially going to complicate rather than remedy. Magnesium is far more important to chloryphyll and fluorescence of green as it forms the core, nitrogen is what surrounds the core, interveinal chlorosis is the biggest tell. Calcium is immobile, magnesium is somewhat mobile because of this plant can dictate where exactly to move the magnesium to more critical growth and will fill the Inside of leaves first this is what gives interveinal chlorisis its distinctive markings. Root cause not sure without full diary bit generally happens when your feeding more than plant is using, this is normally down to environmental factors thay are often overlooked.

Hi it could be nitrogen or zinc deficiency maybe try this if you not already got it Advanced Nutrients Revive, I had similar problem and this seem to helped a lot. https://www.advancednutrients.com/products/revive/