even during normal watering / feeding don"t let water sit in saucers ? what do the white flood trays look like . and where can you get them? do you have them on ur site ?
Thats stupid, use the saucers, when you water the plants, the water will collect in the saucer, then test its ppms to make sure its completely flushed, then dump the remaining water out of saucers, saucers make it so u can move you plants around, with a drip tray you dont have this option. if you water is testing any higher then 500 ppm and .6 ms then you need to keep flushing, trying using R/O water it makes the process much quicker, and the end product will be much more flavorful.