Hi,
thank you all for your advises.
I have switched to CANNA Aqua Vega fertilizer, which is designed for circular systems. This Kratky´s method is not quite circular, but i suppose it will be all right. I also obtained other option for hydro from CANNA - Coco - for flushing method system as described by vendor.
I have changed solution in all tanks for Canna Aqua Vega. After several days most plants were visibly better, but some were still struggling. For those in worst shape i have decided to go for hempty buckets (about six of them) as advised by you guys.
Buckets contains perlit + vermikulit mix (ratio cca 5:2) and i have used Coco fertilizer on them.
Those placed in buckets never recovered, they did not die, but are in quite bad shape and are not growing. I have been thinking that maybe i did too small holes, or maybe placed holes too high. Jiff is about 5 cm big and two holes are at 7cm, therefore it should prevent plant from drowning, which should be main idea in this.
Plants were placed there with small to none roots, they cant drink much, so i might overwater them even with small amount of water.
Now i think that main reason might be mold Trichoderma as it is bloomed recently.
It is added sometimes to coconut fiber. Perlit is clean, but vermikulit is likely infested with it. I discarded its packaging after usage, so i can not be sure though.
I do not quite know how i should measure pH in hempty bucket in order to do some basic troubleshooting. My tip is that mold changed pH from the very beginning. Or could remains of organics fertilizer started to mildew? At this point i am questioning myself if it is even worth to try to save those in hempty. It is no use, if you compare them with their luckier siblings they are just too way behind. Would you do differently? If so, why?
4 plants, which were also a little bit behind, obtained air pump. I do not see significant acceleration in growth in comparison to plants without air. I am not quite sure if i am using it correctly though - pipe is floating on surface, but maybe it should be attached to bottom, so air would make its way to root underwater? What do you think, please?
Rest of plants (about 65j% of all plants) created nice roots and are thriving quite good.
I will continue with passive hydroponics, as most are thriving, but i realized that it wont be so much passive anymore as plants gets bigger and hungrier.
First plant emptied its bucket and before i realized it, it started to drying up.
I had 25 plants, several examples from altogether 6 different phenotypes. Luckily i have well growing plant from each.
Plants had many stresses from the very beginning causing them to strive.
First they were several hours in plastic sacks during transport after i obtained them and right after then were placed into organic solution and left there for several days. Some were drowning or on the contrary surface of their solution was too low.
Hopefully i wont stress them more, but there are still many things i am not sure about.
I have been wondering about amount of fertilizer. I follow instructions - Aqua Vega - i am using two bottles, same for growth and bloom. Both should be mixed with water in ratio 20 mL / 10 L.
Tap water, i am using, has about 7pH, so i add a little bit less to achieve around 5,5pH. I think that is correct as pH is rising only slowly and plants seems to be alright.
Next i want to install fans and net, both to boost plants endurance, so they do not break down under weight of ripe flowers.