Systemic was Confidor,
Currently I have Thrip and Lacebug, mostly on those in semi shade or on those with dense foliage.
I fertilised with Powerfeed and Seasol, but the difference this year was Azalea food and a manure based pellet made by Ktec, the Ktec may have been the culprit and delivered a dose of phosphorus and burned the foliage and roots but not all of the plants have the effect of foliage burn. The bark stays green even if there is complete foliage drop and new foliage will appear. In some cases there is branch drop and part of or all of the plant may die.
It has taken some time for it to appear (2-3 months) and as I mentioned earlier, those with chlorosis seem to be affected or chlorosis is a symptom?
So to summarise a little, it does not affect a particular variety although some are more sensitive than others and yes I have aimed to keep them in a nice open mix,(6mm pine 50%, Zeolite 5%, 5mm pebble 20-25%, and 20-25% perlite or Diatomite) learnt that lesson years ago with Canadian Peat.
I believe that I have lost one nice advanced plant which is quite frustrating,(it is in first aid sitting in coarse sand) I do not want to loose any more.
I hope this additional info will help a little more.
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Both of these were healthy before application of ferts, I put the Azalea fod on after the pelletised stuff to treat the chlorosis as well as iron chelates, these have worked but I still face the issue of foliage burn, I am hoping that the problem will be lessened with each watering.
As far is watering goes, I water as the soil becomes dry, some obviously are dryer than others due to their aspect or variety.
Still scratching my head and will probably go back to Neutrog and organic soluables including Comfrey tea, I used it years ago and did not lose a single plant.
In the meantime I will be doing some more first aid.
Any solutions on this problem are welcome and I thank you all for your recent contributions

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