The quality of irrigation water is essential for good cultivation.
Where you live, the water is bad for plants a PH over 8.0, as well as leaving annoying whitish spots on the leaves, with time lime crystallizes on the traditional suffocation.
For crops it is essential to use rainwater, properly treated and brought to optimal values, or reverse osmosis.
The first forces us to a collection, taking care not to contaminate it, store it, etc.
For convenience I opted for reverse osmosis, use at ppm 50 and PH 6.2 (optimal values ​​for almost all orchids, except for some exceptions, eg paph bellatulum, which likes a higher PH, about 7.0).
For fertilizers, I prepare three different concentrations to support the exogenations of the various species, force 1, ppm 300, force 1/2, ppm 150, force 1/4, ppm 80.
Ppm 300 for Phalaenopsis;
Ppm 150 for dendrobium, some bulbophyllum and almost all paphiopedilum (some require smaller concentrations, such as micranthum and particularly sensitive ones, so that the roots of roots are not run off, it is advisable to run the solution after about two hours of administration).
Also the paph. They splatter on calcific and no, the bark is prepared in a mododiversity, but this is another topic.
Ppm 80, for many rafts, for Chiloschista minor concentrations, or for Scaphosepalum Rapax I do