Starting my DWC over...

[anongreen]

So, I started with six plants and now I'm down to ONE healthy plant O_O. The rest either crumpled up and died, or had their bottommost leaves turn yellow and get crusty on the tips, and slowly yellow the leaves almost all the way to the new growth. I've checked my ph everyday, and adjusted it to about six every time. They've been growing for nearly three weeks, yet the tallest they've become is four inches, with about three internodes worth of growth. I've had algae problems, also. White slimy crap. I've tried to treat with H2O2, but it hasn't helped much.

I just started germinating six new seeds, and I want to do it right this time. Clean out the DWC's head to toe, and get them in perfect working order. Is there a list I can follow for a fool proof way to get some healthy plants through DWC? Put them in the DWC later, not so early? Give them nutrients earlier? Get a better airpump?

Here's a list of what my grow was:

Nutrients: General Hydroponics, Lucas Formula, 1/4 strength since they were small
Light: Two 105 watt (real wattage, not incandescent equivalent) CFL's, 6500k spectrum
DWC: One bucket that holds seven gallons woth of water/solution, holds six plants
One bucket that holds three gallons worth of water/solution, holds six plants (switched to this one, as not to waste nutes)
Airpump: 40 gallon capable pump, hooked up to three big airstone discs.

[Konon]

Looks good. I'd bury those rockwool cubes in the clay balls to keep light off it. Roots might come out of the sides near the top and light for roots = no good.

What kind of water are you using? Tap water contains chlorine = no good. Use distilled water if you are.

Personally, I only use water in my system until they are 2 weeks old, before i begin using nutes at about 1/4 strength. Then I'll up the dosage of nutes weekly by 1/4 str until full str after 5 weeks or so.

How often are you watering and how much?
You are either overwatering or you got some nute burn.