First time running 6 inch rockwool cubes + netafim emitters (Micro-Grow Lab) How much do I fertigate????

My pump is plugged into a Smart Wifi Switch. Given this setup (seen below) of:

-pump at 1800L/hr max pump
-4 (not 3, 1 more coming) emitters
-at this seedling stage
-I had soaked them in nutrient solution for 45 min. today before transplanting, (they were very heavy, so I moved them sharply in the air, to let some of the excess runoff out)

What are your best recommendations please:

1. Approximately how much should I irrigate now?
2. How long do I program the smart switch to turn-on per day during this stage?
3. Do I measure it by time, or flow as calculated, or runoff as measured in an amount or percent etc.?
4. What is the optimal frequency?


Chat GPT recommended a lot of water:
"Start with short cycles: Since your seedlings are only a few days old, it's important not to overwater them. Begin by running the pump for short cycles of 15-30 minutes, two to three times a day. "
This sounds like too much?

Note: the water is not being recycled. This is drain to waste! However I dont want to waste tooooo much. Since this is a trial for a much larger commercial operation where we will use rockwool....

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ignore chat gpt unless your goal is to kill them.
15-30 minute "short" cycles...no. no cycles now.
your block is already saturated, you dont need to add more.
how much do you think that tiny seedling is drinking?
I'll feed about 200 ml every other day starting at 4 or 5 days after going into blocks.
pour it in a ring out from the plug, avoid wetting the seedling directly.
I'm a couple weeks in 6x blocks before going on auto feed.

if you feel your block is "too wet" set it on a small folded towel (anything absorbent) and it'll wick out quickly.
same for the rockwool plugs.
squeezing, shaking, etc. can damage it.
think of a cotton candy like structure but made of stone.

pic is transplant size, 14 days from seed works good for me.

With any grow medium like that you want to find where it "dries back" aka almost gets dry, then find out how much water you need in seconds before they runoff, once you can time those 2 events through the grow you will be in good shape.

Obviously as plants mature and grow larger you will need to increase either the interval or the duration of watering.

Also, if your environment isn't stable then you will need to further tinker with intervals.