1st Hydro attempt. Frazzled seedling!! HELP.

white pebbels? i have a a bucket of hydroton rock that have been sitting ousside in 80 90 degree temp for a month now that are still red. maybe im stupid and you alread adrees this but it sounded to me like salt build up and maybe over fertazling...over ferting can cause narly burns in your plant. i had the same problem in my hydro setup early in vegging my babies. i just flushed the system with 3 days of only water feeding constanly checking ph each time. if you use a liqued ph tester which im sure you do you want the color of the water when you test it to look like a dark yellow somewhat like when you take a piss after holding it in for awhile

absolutely fantastic response matey. salt build up, it's what the man at the growshop told me it maybe too. I'll have to check properley soon (got to time my visits perfectly!). I'll definately try flushing it too, sounds like a great idea. many thanks for the advice. cheers.

did u prepare your pebbles before starting the system? i.e. wash them, and soak them before hand (what I got told..)
Cheers

It's white due to salts, so your plant withered to to toxidity...you don't have light too close if you are 18" away...a 250hps is not too much light...distilled water is usually a ph of 7, just like any other "cleaned water"

for those of you who asked about soil ph measuring...water and allow run-off to over flow then take ph reading of overflow...after fluid drains through completely...

did I miss anything?

Thanks everso much. Any advice on preping the pebbles?
Cheers

I wash them with dawn w/bleach and rinse the Hell out of them, then soak them overnight in Florakleen...it will dissolve all the salt build-up...peace

New ones just need to be rinsed 3-4 good times until red dust water runs clear...

Latewood, thats fantastic mate, just the advice I've been looking for.

Just washed the pebbles off. It's amazing how much red dust came off into the water, andf the salty crap that was left. Got them soaking over night in the tank. I think I'll run the system, drip ring and all, for a couple of days with just water. Flush everything out. Has anyone used the setup I'm using before? Latewood, did you use a drip ring? Love to hear if anyone has.
All the best.
(can't wait til I create some 'natural' medicine for the 'ol arthritis!)