Thanks for the info I don't know if this might be of intrest to you or not, again i,m using 35 gal. tubs, a circullator fitting on my submersible and 2 of the expensive ceramic air stones for 6 plants. I started getting a snotty slimey looking substance on my roots and I couldn't figure out what it was, 1 year later the only thing I come up with is the europonic hydro fertilizer....mabey a bad batch?, or this might be a problem with the new d.w.c. systems. Anyway thought you could use the input.....Thanks again.:jointsmile: