How long , generally, does it take for the roots to reach the water in a DWC grow? I have 4 healthy looking BigBud autos @ 10 days of age with no roots protruding from the net pots yet... they were planted directly into Coconut Coir Netted Seed Starting Pellets and are probably 3" tall and have several set o leaves. They have been on RapidStart since about day 5 and had been top watered until day 8. This is only my second time with hydro, so I'm still trying to figure it all out...
Were these branches cut from a mother plant and now you're trying to clone them into deepwater culture?
I germinate a seed with whichever method works well for you. On ce the seed has a tail over a quarter of an inch long I transfer my seed to a sliver of rapid router. Leave the tail of the seed almost protruding from the rapid router put it in your basket raised by your rocks or whatever you're filling your basket with I raise it to where the rapid rooter does not stay soaking wet. Very important make sure there's a fan blowing above the rapid router to make moisture evaporate upwards and within 5 days you'll have a root in the water. PPM on my water is about 100ppm a smidge of calmag and a pH of around 6. this is just what works for me over and over again.
It looks like you give the a little more of a head start than I did, my taproot will have to make it through a bout an inch and a half of coco and another two inches or so of hydroton to get out of the bottom of the net pot... The first week the water onl had a touch of CalMag and PH around 6. starting the second week at about 450 PPM (General Hydro Flora) Rapid start and Hydro guard... keeping the PH around 6. This is how they currently look:
I use rock wool and transfer when the bottom looks like this. About one week after they sprout. It takes a few extra days but you get a bunch of roots that drop into the water at the beginning instead of just one.
@Jaboc33 , That is very interesting. I really do just get one single root that drops into the water within 5 days. In time I get many roots. Some people do really well with rockwool. Would you top feed with rockwool? OP, I was taught the seeds only thrive shortly after germinating and you need to get roots started within days 450 nutrient strength is too strong for seedlings without roots. I don't top feed but I make sure I've got water boiling below that keeps my basket dripping. I also don't do cocoa just red rocks.
I personally only top feed with a 100ml syringe maybe once. Otherwise the bubbles in the bucket keep everything wet until the roots drop. I have great luck with rock wool.
I have roots, obviously, they are pulling water / nutes from the clay at this point. I don't see any nute burn, they look fairly healthy overall.