I believe it might b the hempy bucket method. Don't quote meet on that as I'm a noob but from what I understand you water until run off in order to alleviate any access salt buildup your medium may contain. When the salt build up is flushed out it is still at s much more concentrated level then when put into the medium so I'm wondering if the reservoir of your buckets is maybe holding a hot mix? I don't know much about this style growing but if the hempy buckets from what I understand almost create a reservoir, like dwc, or might also have to b maintained and watered less often and less nutrients as to avoid to much concentrated nutes in the reservoir. Also do you have to keep the reservoir area temperature with a specific zone like dwc maybe? Just taking shots in the dark to try to help fellas. Sorry if it doesn't