Changing from coco coir to rockwool

[Slippy81]

Hi everybody,

I have been growing weed in coco coir for these past 5 years. Its had its ups & downs but overall I am satisfied with the results. I researched a bit on growing in rockwool. My setup is a grow tent with 3 partitions (seedlings / clones, veg & flower). The flowering area is 1.2m x 1.2m by 2m height. I have 2 light fixtures with citizen CLU 048 cob lights totalling to almost 500w and 1000 ppfd. I regulate temp and humidity easily with a dehumidifier and a temperature controller, maintaining the VPD to approximately 1 (temp around 24/25 degrees and 60% humidity during flower).

Last grow, I tried drip irrigation with this simple system from GIB Industries:

GIB Industries Irrigation Kit (8x drippers & pump) - for 8 plants

The 8 drip irrigation system is a complete gib industries drip irrigation system

www.growtent.eu

Having an automated setup for coco simplified a lot and made my life much easier.

Now I will be trying to grow with rockwool from Grodan.

Can you suggest the size of the rockwool cubes to grow 4 plants? As the veg area is smaller,do you think 4 inch cubes are enough? Was thinking to start with this size and then stack them on the Hugos. Is the drip irrigation that I have, good for rockwool?

I never exceed 1.3ec with coco. Are the EC / PPM requirements same for rockwool?

Thanks in advance.

 

[Paratwice]

Some Rockwool growers should chime in here. Seems like your within the parameters though.

 

[Dr.Green55]

2.5 x4 x4 on top of a 6x6x6 will work fine, I prefer 2.5x4x4 on top of a uni-slab. Rookwool can be used very simply or can be used very technically meaning with inputs/meters etc. when I started out with Rockwool I knew shit, but now I run it far far different then I did, and I can tell you Rookwool is only going to put out based on how its run . if your just going to run it simply its probably not going to produce any better or as well as sunshine or coco. its inert it requires some dialing in of nutrients to work best, and its easier to have root issues with it as opposed to soil or coco . My first grow with Rookwoo was really no better then soil, but I seen its potential and started playing with, Rookwool is all about maintaining, PH running proper ec, number and amount of shot sizes and duration through P1 P2 and P3 a lot of that will depend on if your looking for quality or mass. so stacking the ec in the medium is very important, how you do it, how fast you do it and how much. That EC will all depend on you lighting and environment and is not going to be the same as coco, runoff will control PH and EC, so the idea is stack P1 more short shots off nutes, P2 maintain, with runoff only starting at the end of P2 and a P3 if needed. I do not concern myself with dry backs , maintain pressure PH and EC is far more important , I start out with 1.1-1.2 ec right out of the cloner, depending on the phase and where I'm at in the grow I'll stack to 3 ec no issue . whether you run generative or vegetative will make a difference in the above. it will for mass and quality as well. depending on light scheduled 18 or 12 I feed 25+ times a day, so an automated setup and good timer comes in handy.