rockwool & clay pebbles irrigation frequency and transplanting question

Hello!

Its been 5 days since ive planted my germinated seeds into 1 inch rockwool cubes.

Ive read and it makes sense to water the rockwool cubes when the cube is almost dry. In my experience that means: like every 3-5 days on start, and like 1 or 2 times per day in 2 weeaks after start (when root mass is bigger and it consumes more).

Next step im planning to do is to wait untill roots are developed enough, and then transplant them into 3 inch net pots filled with clay pebbles and this is where it gets tricky for me, cause im not sure how often and how should i water this new root zone that now consist of 2 different mediums.

I dont want to irrigate to often, cause i want the rockwool to dry out a bit between waterings so that roots dont suffocate. I guess that rockwool cubes needs at least like 12 hours to dry out and get some frest air...

But i want to irrigate often enough so that clay pebbles dont dry out between waterings. Ive read somewhere that irrigation cycle for flod&drain should be about every 15 min or so...

So...im not sure how often should i irrigate when i transplant into net pots. ...Specially at those fist days when the roots and everything is still weak...

this is my 4th attempt/crop since ive decided to try hydro. all 3 prevoius attempts wore a failure. Seems like I always have root rot

anyway...attached image contains sketch of my sistem. I guess its some kind of a hybrid NFT/top feed system, with everything hooked on arduino microcontroller. Does this system have any foundamental mistake im not aware of?

...What would be the best way to get from 5days old seedlings in rockwool cubes, to plants in netpots with clay pebbles that are ready to be transplanted in this kind of system??

Any help would be mucho appreciated. Cheers!

Hi.. Let the seedling root well in the initial block then once you transferred to clay balls you can increase the watering frequency,the block will be fine has the roots have fully colonised the block and wont suffocate.once in net pots you can drip feed constantly or flood the net pot every 15 mins without problems.

Net pots with a rockwool cube I water 4-6 times a day (lights on) to start and increase if drying too much in between cycles.

Main thing about seeds in rockwool is to avoid damping off. Make sure to have a fan blowing lightly and indirectly on the seedlings.

Thanks for replay azad and lester!

Ive just googled what damping off is, and looks like it is mostly caused by pythium, witch is root rot if im not mistaken?

while i never had problems with damping off in rockwool before, I had problems with root rot in all my 3 previous hydro attempts.



This is how the roots looks now. some of the roots are getting somewhat brown/yellow at the tip. Is this a sign of weakness? I have lifted rockwool cubes a bit, so the bottom side is exposed to air, so the roots are getting air pruned. I guess that shouldnt be a problem? I guess the roots need a couple more days to be ready for transplant?



Ive already transplanted one into netpot(too early i guess), and this is what it looks like besides its final destination in an automated system. I also made a cover for netpot, so the light cant go in, and moisture cant get out

So...when i eventually put them all into system(In about a week i guess?), i want to water them like 2-4 times/day on start, and like every 5 min(for 30s) when full flowering?

I dont want the pump to run continuously cause of noise/heat, and i cant flood the netpot. Is this a problem cause maybe dry pockets in netpots can apear?

Thanks again for respond!

...also...if someone can correct my thinking...

I guess that pythium is (unless in real sterile condision) more or less always present. Its just that it only attacks weak and dead roots?

So if I get sudden dry pockets somewhere in netpot, the root there can dry out, die, and cause a pythium infection ready to grow and spread, among other weak plants? And that can be (among other things...) the cause for one or all of 3 of root rot infections that i had?