OK here is the issue I noticed the leaves were curling yesterday. Assets and found out that my partner put too much nutrients ppm was 890 so I drained the nutrients and cleaned the whole system from head to toe. I use these cut out white plastic covers that I put over each clone covering the net pot completely (see youtube video for room layout) 1st.https://www.youtube.com/watch?v=Xe99SWAHBVs 2nd.https://www.youtube.com/watch?v=VYyEDWRrPvk&feature=em-upload_owner I was replacing one of the plants because it did not look as healthy as another clone I had while I was doing this I noticed very small specs of white powder on the hydrotone/rockwool cube mix medium I use. (I mix it myself ,see attached photo's) At this point I freak out and took all of the white plastic covers off all the plants (The Plastic sheet is the white on one side and black on the other side that you can buy from the grow store)I used it on the walls and ceiling. the white powder was only on 12 out of 32 plant site and in very small amounts. a spec here and there.(see attached photo) the plant sites that had the powder were all wet and the ones that did not have the powder were dry. I hand picked all of the hydrotone/rockwool that had white powder on them out of the 12 plant sites in the morning I will take all 12 plants out of the system and give them a flush with h2O2 then fresh water then transplant back into system. if anyone has a better idea please let me know