want to use organics with rockwool e and b

ok, i have an ebb and flow. im doing 4 trays, 4 lights. 1 veg 3 flower. rotating every 3 weeks. nice sog.
i have no expierience with organic ferts. with the research ive done, ive learned you have to use the solution in 2 days once mixed!
this is what that means for me:
- i use 25gal of water per 3' tray. 15ml of bio flora/ 1 gal of water every 2 days! (thats 375ml/resavoir every 2 days) right?
- a 1 liter bottle is $30. thats 1.3 bottles every 2 days.

What am i Missing?

what kind of organic nutes can i use with a rockwool set up. id like to use the same water for a week or 3! just dose it up every now and again. Is this possible?

I haven't read that, but maybe if the solution is not aerated, you need to use it quickly. As long as you aerate the res, by roiling the surface constantly, you will replace the oxygen that is consumed. You can keep a res for several weeks if you monitor the strength and make adjustments.

I would advise that you start hydro using chemical nutrients, because hydro-organic is just another thing that can mess up.


HTH