hmm, my tap water (well) and my location is of the 7 plus range as well. I do not have the sulphate, but I have been using muriatic acid along with my worm compost tea with good results so far. I know, no answers, just more what if's

Chlorosis in plants has many causes due to lack of nutrients or an imbalance of nutrients. Nitrogen, Potasium, Magnesium, Zinc, Iron, Sulfur, Boron, Copper, Manganese, and Molybdenum deficiencies can all cause chlorosis and excess of any one of those can inhibit the uptake of others. Then if the soil the plant is growing in is too wet, or too dry, the plant will not be able to uptake needed nutrients, or if the plant is "pot bound" the roots will not uptake necessary nutrients.

Is the yellowing prevalent in older foliage or newly emerging leaves? Did you check for mites/scale ...? What are you using for fertilizer? If you're using a soluble fertilizer at regular intervals, it's very unlikely there is a physical deficiency of Fe; more likely something pH induced or some other issue. S deficiencies in containerized plants are rare, BTW. If the plant has been in the same soil for more than a year, and your fertilizer doesn't contain Mg, it's a very real possibility that you're seeing a Mg deficiency. If you suspect a Mg deficiency, try mixing 1/2 tsp of MgSO4 (Epsom salts) in a quart of water and spritzing some of the leaves. If they green up, it was probably a Mg deficiency, but the nice thing about the MgSO4 is that it will also correct any S deficiencies.

There ARE other cultural conditions that can cause deficiencies, but usually, when you start adding a little of this & that to try to correct a singular nutrient issue w/o strong indication of what's wrong, you end up creating problems rather than solving them.

It's better to start from the bottom up, with a close look at your soil, then your choice of fertilizer, because in the end, your soil choice is the most probable source of trouble, if you can eliminate light as the issue.

Al

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