They’re small and idk 3 weeks old, no signs of deficiency aside from blossom end rot.

Was set up with Manutec 1L Hydroponic NK Plus For Fruit And Veg. Water is about half depleted, has been hot so possibly nutrients are concentrated?

pH had risen to about 7 from 6.5. I readjusted it to about 6.5. In dirt this range would be fine for calcium transport.

Oh hydroponic wisdom people, enlighten me. Should I just remix new solution? Add a supplement? Is pH for transport different in hydro?

  • FrostyTrichs@walledgarden.xyz
    2·
    16 days ago

    pH is safe in the same ranges as soil more or less. 5.5-6.5 is where the plants have the easiest time but they’ll tolerate fluctuations outside that range as long as it isn’t wild swings.

    Do you have a way of measuring TDS or EC? Those would give you a better starting point.

    Assuming the roots look healthy-

    There are lots of ways plants can become nutrient deficient. A common one with kratky is low nutritient availability because they are simply being exhausted. I don’t know anything about the nutrient line you’re using but it’s fairly common to have to supplement things like calcium and magnesium for certain plants regardless of the base nutrients. If the growth has been satisfactory and otherwise healthy until recently, it’s likely they are missing key nutrients in the res.

    If you don’t have a way to measure things the easiest thing is to simply empty and refill the res with a fresh nutrient mix and keep a close eye on the pH to try and gauge how quickly they are taking in nutrients vs drinking the water.

    • NaevaTheRat [she/her]@vegantheoryclub.orgOPEnglish
      2·
      16 days ago

      Do you have a way of measuring TDS or EC? Those would give you a better starting point.

      I have a multimeter, a physics degree, a pile of junk, and duct tape. So maybe? No time at the moment to do some garage science though :(

      Maybe if I have a sleepless night.

      Assuming the roots look healthy-

      Giant ball of the healthiest fucking roots I’ve ever seen. Beautiful ivory colour. The growth is kinda amazing actually, not something I ever see in my usual dirt gardening.

      If you don’t have a way to measure things the easiest thing is to simply empty and refill the res with a fresh nutrient mix and keep a close eye on the pH to try and gauge how quickly they are taking in nutrients vs drinking the water.

      I will give this a go. Is there an easy way to measure the specific content of like a particular nutrient? Or does one just sort of assume if the conductivity (I’m assuming EC is conductivity? testing concentration of ions by way of resistance?) is going down replace the whole thing rather than risk imbalance?

      • FrostyTrichs@walledgarden.xyz
        2·
        16 days ago

        Giant ball of the healthiest fucking roots I’ve ever seen. Beautiful ivory colour. The growth is kinda amazing actually, not something I ever see in my usual dirt gardening.

        Awesome. The noodle monsters are one of my favorite parts of growing without soil. Air roots in particular are something I never get tired of staring at.

        Is there an easy way to measure the specific content of like a particular nutrient?

        If there is something reliable and reasonably inexpensive it isn’t something I’m familiar with. I used to use test strips but they aren’t trustworthy IMO so I don’t recommend them. I just watch the plants. Seems like you’ve already got a handle on that.

        Or does one just sort of assume

        I do a lot of this, but I’ve spent a long, long time doing things the hard way because I’m stubborn.

        Measuring TDS and EC gives you a wider snapshot of the health of the solution than pH alone. All three together can tell you a lot at a glance and a deeper analysis isn’t usually needed. If you measure the water you’re using pre and post mixing in your nutrients you’ll have a good idea of what the nutrients are doing to your water and what the overall nutrient concentration “normally” is. Then you can make an educated guess about what’s happening as things change in the res.

        Sometimes (usually most) a simple top up will do, being mindful of the pH swing if any. Whether you’re topping up with plain water or nutrient solution would depend on what kind of readings you get and how you interpret them. You can do the same thing with pH readings but it’s extremely helpful to have those other data points, especially in the beginning.

        Since we don’t know much about your res for sure the safer thing is to start fresh since the plant is in a much different phase of its life anyway. If nothing else you’ll know the plants have the full range of what your nutrient line has to offer while you decide if you need to supplement with anything in the future. The stuff in the res can be repurposed for other plants as long as the pH is decent. Anything in soil will have enough of a buffer to not care about what is or isn’t in the leftover res water.

        If changing the res doesn’t do anything to help with the end rot, or if the problem comes back after a week or two, there’s a good chance that they aren’t getting the calcium they need for this stage of growth. If we assume that things aren’t locked out for some reason, availability would be my next assumption.