Hi Daniel ✌️ You helped me with germinating some old seeds a few months ago & I was hoping u can help me with something else this time if u don't mind. If u grow hydronically using coco as a medium & ur run off is allways with in 200 & 300 parts per million eather side of intake ec do u really need to flush weekly? Or can u give them plain water every 7 days double ur normal fertigation amount & follow up 1 hour later with a normally full strength feed? I would appreciate ur reply champ. Thanks again Da I'll. Allso in peak bloom period should u feed daily when lights on or every other day? It's canibus Sometimes I'll feed daily 30 min after lights on & sometimes a feed every 2nd day. I think they like the dry back??? day LOUIS😊
This was an excellent video on this subject. I just chopped 4 cannabis plants, first time running a coco/20% perlite medium (previous amended coco or soil). Didn't water to much runoff throughout the grow But at chop when I did a water flush the runoff ph was super Low (mid 4's) (fed 5.8 in veg/ low 6 in flower)and EC was crazy high (high 5's when I was feeding less than 3.0). The plants finished nicely with an impressive fade and dense buds But those numbers had me shocked and says I need to water to significant runoff in that form of medium and I need to monitor it throughout the grow. Any thoughts? I'll stop by your Instagram and follow ..
Hello Daniel. First off thank you for all your information freely available it helps so much. So after the flip/stretch I am noticing PH swinging way too high in conjunction with a clear accumulation of No3. So I pulled CalNit. I did a defoliation to try and swing plant morphology more generative by increasing sink load. I’m also watering @ 5.5 and bumped potassium up in my regimine, increasing frequency while slightly lowering duration of irrigation events to ensure more runoff delivered at a slightly slower pace. I increased the room temp slightly along with slightly raising the humidity. In hopes of raising plant metabolism while slowing transpiration to help translocate and “use” that excess no3 while treating the root cause. Does this sound like a sound approach? Thanks!
How does this information fit in with the new "crop steering" techniques being embraced by the cannabis community that use so-called "generative" steering by watering up to field capacity but not actually to runoff? Do the substrate sensors used in these types of crop steering systems replace the need to measure the runoff? I have the substrate sensors in my facility but I don't really trust them fully. Do you recommend watering to 20% runoff during the entire flowering phase (cannabis)? The new crop steering techniques recommend no runoff during certain periods of flowering. I find this conflicting info confusing as a beginner. Thanks I enjoy your videos.
You can always do no runoff for most of your plants and then hand water a single plant till you get 20% runoff to see how the media environment is. Watering with no runoff is environmentally friendlier so formulating and growing with no runoff - for all plants in general - can be better. However, to monitor the root environment pH and EC, getting runoff from single plants daily can help a lot. You need to pay attention to salt accumulations though as many formulations do not play well with low runoff regimes as they tend to contain a lot of P, Ca and S.
thank you for posting sir. i just have a question about feeding. does input ppm need to be the same as substrate ppm? im vegging in new soil and run off is 1800-1900ppm after a couple weeks of plain water. im noticing dark leaves curling and a copper dot with a burnt yellow tip. im not sure if i should keep flushing plain water or add a compost tea at 1800 to feed. any input would be very helpful and much appreciated.
For an inert media usually runoff conductivity will be higher than input conductivity, if they are the same it usually means that either the ratios are not correct or the amount of nutrition is not enough. However if you are in soil this does not apply as the soil nutrient contribution needs to be taken into account. To properly address your problem you will need a soil analysis and proper formulation of both the soil amendments and any nutrient liquid feed.
Saludos Daniel , gracias por el programa. la información es muy valiosa y debidamente soportada por ciencia. Quería saber que fuente bibliográfica es útil para buscar EC óptimos para cannabis u otras plantas de interés económico.
Gracias por tu comentatio. No existe un "EC óptimo" ya que la conductividad de distintas soluciones varía según su composición. Así mismo, cantidad óptima de nutrientes en una solución depende también de factores como la temperature, la luz, la suplementación de CO2, etc.
hi Daniel I am growing I am growing in coco coir and my runoff ph is consistently above 7 . 7-7.3 I use rain water , canna a and b nutrients. and I ph to 5.8 but it comes out at 7+ . I flushed one of my plants with pure rain water which is ph5.5 and got the ec down to 300ec before I stopped but the runoff was still 6.9ph . my usual runoff ec is within 100ec lower than input ec. so I feed 1.2ec and I get 1.1 out . I use citric acid to lower the ph . I had to feed with a ph of 4.6 to get the ph runoff to be 6.0 . is it ok for me to feed at 4.6 to get runoff in range ?
Thanks for writing. Feeding that low is not normal, make sure you never feed below 5.5 as this can hurt plants. The problem is the balancing of your chemistry at the root zone. Citric acid - or other organic acids like lactic, acetic, etc - should not be used to lower the pH as it will actually cause it to increase even more aggressively after. Lower your pH using sulfuric acid. Also add 20% of the nitrogen your plant needs as ammonium and not nitrate. Once you make these modifications your root zone pH should stabilized. However, for a more thorough evaluation of your current situation please consider booking an hour of consulting time.
So, if our runoff pH is > 6.5 we should irrigate at pH 5.5. I imagine this is because if we acidify the solution more we move away from excessively high runoff ph values. But in this way we are not also going to neutralize even more the carbonates / bicarbonates making the solution highly prone to ph fluctuations?
Thanks for commenting. The idea is to shift all the buffering capacity of the solution so that we can react with bases. You do neutralize some of the carbonates in your water by doing this, you turn them into carbonic acid, which is also working in your favor as it can react with bases. They will turn into bicarbonate again once they neutralize the basic pH in your media. This is especially true if there is little time for carbonic acid to turn into CO2 and escape (for example if you have an injector setup and are irrigating quickly after setting the pH of the solution). So, we're shifting all reactive capability of the solution (phosphates and carbonates) towards the acidic side (forming dihydrogen phosphates and carbonic acid).
@@stefano5080 The difference between inlet and outlet PH is not indicative of the rootzone ph. If you run PH 5 water in and get ph 7 water out.. your rootzone is not PH 6, it is much higher.
Thanks for writing! That will be the topic of another video. For recirculating systems there are three different management techniques I use that can be applied, depending on your constraints. Keeping the EC constant in these systems is trickier because we must be sure not to over-add nutrients that accumulate in solution. So you can keep the EC constant, but when needing to increase the EC you should use a replenishing solution that is different from the solutions used to prepare the original nutrients.
@@ScienceinHydroponics and this solution would primarily be nitrates, potassium, and manganese with low level of Phosphorus if I remember from your previous video?
@@ScienceinHydroponics that makes me think of how aeroponics could actually be advantageous as it sends the ions directly to the roots with low overall runoff. Possibly forces an equal rate of uptake.
In my opinion, with recirculating systems, you should run them exactly like a hydroponic deep water culture reservoir. You either occasionally dump and restart your reservoir to avoid buildup/deficiency, or you do sample tests to determine which salts specifically need to be replenished.
Hello Dr. Fernandez, thank you so much for sharing your knowledge with us. I would like to add some suggestion for videotopics, that, to be true, mainly consist of questions I was not able to solve myself to date. - Does the salt used for creating liquid fertilizer can have an impact on the expression ([pure white, ]almost white, very bright yellow, […] almost yellow[, pure yellow]) of the chlorophyl-free parts of the leafs of (albo|aurea) variegated plants? - I would love to see a Kratki tomato long time measurement project that shows the impact of Carbamidenitrogen to the pH when using RO water in comparison to your other fully-passive Kratki tomato that I assume was fed only Nitrate and Ammonium. I am suggesting this, because many people use those „made for hard tapwater“ liquid fertilizers in (semi-)hydroponic RO setups and end up with epic battles against acid drops fighting them back with sorts of rehardening materials like eggshells or by adding pH buffers. And could you please consider buying a professional glue gun before building another Kratki? 😉 - Could you describe a way to create your own liquid (single, two part, three part) fertilizer from liquid mono-fertilizers at the example of „canna mono“ products, taking the limited information into account endusers usually have about those products. I am asking this, because most people have easy access to liquid mono-fertilizers, but not to the salts, or they can not afford the overhead costs of their own production. Maybe, if you like the idea of a wider spec. (semi-professionals or enthusiasts) of people using Hydrobuddy, this could become an additional calculation mode. I hope my questions and suggestions are not too basic or of the „you would not do it this way“-type or from the unprofessional side. Otherwise I would be more than happy for hints and keywords about how or where to find information to answer the questions myself. ✌🏻
I really feel like I'm going to have a completely different yield after watching your video. So thank you for providing your knowledge to the community. I would like to ask: When using soil, would you still want to use the run off to measure output pH & EC, or would you recommend performing a slurry test with the soil closes to the root environment? Thank you for your time.
Thanks for commenting! I'm glad you enjoy the content. When using a soil you still want to perform an EC measurement of the runoff. However, the soil - depending on how it's amended - can contribute a lot of substances that do not register in an EC measurement because they are not ionic in nature (like sugars for example), so the runoff of a soil can be at equivalent osmotic pressure at a lower EC.
Internet gold
Hi Daniel ✌️
You helped me with germinating some old seeds a few months ago & I was hoping u can help me with something else this time if u don't mind.
If u grow hydronically using coco as a medium & ur run off is allways with in 200 & 300 parts per million eather side of intake ec do u really need to flush weekly?
Or can u give them plain water every 7 days double ur normal fertigation amount & follow up 1 hour later with a normally full strength feed?
I would appreciate ur reply champ.
Thanks again Da I'll.
Allso in peak bloom period should u feed daily when lights on or every other day?
It's canibus
Sometimes I'll feed daily 30 min after lights on & sometimes a feed every 2nd day. I think they like the dry back??? day
LOUIS😊
This was an excellent video on this subject. I just chopped 4 cannabis plants, first time running a coco/20% perlite medium (previous amended coco or soil). Didn't water to much runoff throughout the grow But at chop when I did a water flush the runoff ph was super Low (mid 4's) (fed 5.8 in veg/ low 6 in flower)and EC was crazy high (high 5's when I was feeding less than 3.0). The plants finished nicely with an impressive fade and dense buds But those numbers had me shocked and says I need to water to significant runoff in that form of medium and I need to monitor it throughout the grow. Any thoughts? I'll stop by your Instagram and follow ..
Hello Daniel. First off thank you for all your information freely available it helps so much.
So after the flip/stretch I am noticing PH swinging way too high in conjunction with a clear accumulation of No3. So I pulled CalNit. I did a defoliation to try and swing plant morphology more generative by increasing sink load. I’m also watering @ 5.5 and bumped potassium up in my regimine, increasing frequency while slightly lowering duration of irrigation events to ensure more runoff delivered at a slightly slower pace. I increased the room temp slightly along with slightly raising the humidity. In hopes of raising plant metabolism while slowing transpiration to help translocate and “use” that excess no3 while treating the root cause. Does this sound like a sound approach? Thanks!
Keep the videos coming. And thank you for you knowledge 🙏 🌱🪴🌴💚
only just found your channel the other day, I am blown away by the wealth of knowledge you have, cheers mate!
Thanks! I am happy to hear you like it.
How does this information fit in with the new "crop steering" techniques being embraced by the cannabis community that use so-called "generative" steering by watering up to field capacity but not actually to runoff? Do the substrate sensors used in these types of crop steering systems replace the need to measure the runoff? I have the substrate sensors in my facility but I don't really trust them fully. Do you recommend watering to 20% runoff during the entire flowering phase (cannabis)? The new crop steering techniques recommend no runoff during certain periods of flowering. I find this conflicting info confusing as a beginner. Thanks I enjoy your videos.
You can always do no runoff for most of your plants and then hand water a single plant till you get 20% runoff to see how the media environment is. Watering with no runoff is environmentally friendlier so formulating and growing with no runoff - for all plants in general - can be better. However, to monitor the root environment pH and EC, getting runoff from single plants daily can help a lot.
You need to pay attention to salt accumulations though as many formulations do not play well with low runoff regimes as they tend to contain a lot of P, Ca and S.
You're a genius Mister.
This is brilliant. Thanks so much. Learnt a lot
Glad it was helpful!
thank you for posting sir. i just have a question about feeding. does input ppm need to be the same as substrate ppm? im vegging in new soil and run off is 1800-1900ppm after a couple weeks of plain water. im noticing dark leaves curling and a copper dot with a burnt yellow tip. im not sure if i should keep flushing plain water or add a compost tea at 1800 to feed. any input would be very helpful and much appreciated.
For an inert media usually runoff conductivity will be higher than input conductivity, if they are the same it usually means that either the ratios are not correct or the amount of nutrition is not enough. However if you are in soil this does not apply as the soil nutrient contribution needs to be taken into account. To properly address your problem you will need a soil analysis and proper formulation of both the soil amendments and any nutrient liquid feed.
Excellent, excellent information, thanks and keep the education coming!
Thanks, will do!
Excellent video, thank you so much for the information and clarity!
Glad it was helpful! Thanks for watching!
Saludos Daniel , gracias por el programa. la información es muy valiosa y debidamente soportada por ciencia. Quería saber que fuente bibliográfica es útil para buscar EC óptimos para cannabis u otras plantas de interés económico.
Gracias por tu comentatio. No existe un "EC óptimo" ya que la conductividad de distintas soluciones varía según su composición. Así mismo, cantidad óptima de nutrientes en una solución depende también de factores como la temperature, la luz, la suplementación de CO2, etc.
Thanks for the information from me also keep doing what you doing we love jt
Much appreciated
hi Daniel I am growing I am growing in coco coir and my runoff ph is consistently above 7 . 7-7.3
I use rain water , canna a and b nutrients. and I ph to 5.8 but it comes out at 7+ . I flushed one of my plants with pure rain water which is ph5.5 and got the ec down to 300ec before I stopped but the runoff was still 6.9ph . my usual runoff ec is within 100ec lower than input ec. so I feed 1.2ec and I get 1.1 out .
I use citric acid to lower the ph . I had to feed with a ph of 4.6 to get the ph runoff to be 6.0 . is it ok for me to feed at 4.6 to get runoff in range ?
Thanks for writing. Feeding that low is not normal, make sure you never feed below 5.5 as this can hurt plants. The problem is the balancing of your chemistry at the root zone. Citric acid - or other organic acids like lactic, acetic, etc - should not be used to lower the pH as it will actually cause it to increase even more aggressively after. Lower your pH using sulfuric acid. Also add 20% of the nitrogen your plant needs as ammonium and not nitrate. Once you make these modifications your root zone pH should stabilized.
However, for a more thorough evaluation of your current situation please consider booking an hour of consulting time.
Microbes doing it
So, if our runoff pH is > 6.5 we should irrigate at pH 5.5. I imagine this is because if we acidify the solution more we move away from excessively high runoff ph values. But in this way we are not also going to neutralize even more the carbonates / bicarbonates making the solution highly prone to ph fluctuations?
Thanks for commenting. The idea is to shift all the buffering capacity of the solution so that we can react with bases. You do neutralize some of the carbonates in your water by doing this, you turn them into carbonic acid, which is also working in your favor as it can react with bases. They will turn into bicarbonate again once they neutralize the basic pH in your media. This is especially true if there is little time for carbonic acid to turn into CO2 and escape (for example if you have an injector setup and are irrigating quickly after setting the pH of the solution).
So, we're shifting all reactive capability of the solution (phosphates and carbonates) towards the acidic side (forming dihydrogen phosphates and carbonic acid).
@@ScienceinHydroponics thanks
@@stefano5080
The difference between inlet and outlet PH is not indicative of the rootzone ph. If you run PH 5 water in and get ph 7 water out.. your rootzone is not PH 6, it is much higher.
Great stuff
Thanks for commenting!
For recirculating systems, how do you manage the EC? Do you aim to keep it at a steady level?
Thanks for writing! That will be the topic of another video. For recirculating systems there are three different management techniques I use that can be applied, depending on your constraints.
Keeping the EC constant in these systems is trickier because we must be sure not to over-add nutrients that accumulate in solution. So you can keep the EC constant, but when needing to increase the EC you should use a replenishing solution that is different from the solutions used to prepare the original nutrients.
@@ScienceinHydroponics and this solution would primarily be nitrates, potassium, and manganese with low level of Phosphorus if I remember from your previous video?
@@ScienceinHydroponics that makes me think of how aeroponics could actually be advantageous as it sends the ions directly to the roots with low overall runoff. Possibly forces an equal rate of uptake.
In my opinion, with recirculating systems, you should run them exactly like a hydroponic deep water culture reservoir. You either occasionally dump and restart your reservoir to avoid buildup/deficiency, or you do sample tests to determine which salts specifically need to be replenished.
@@SetTheCurve what testing systems do you use?
Hello Dr. Fernandez,
thank you so much for sharing your knowledge with us.
I would like to add some suggestion for videotopics, that, to be true, mainly consist of questions I was not able to solve myself to date.
- Does the salt used for creating liquid fertilizer can have an impact on the expression ([pure white, ]almost white, very bright yellow, […] almost yellow[, pure yellow]) of the chlorophyl-free parts of the leafs of (albo|aurea) variegated plants?
- I would love to see a Kratki tomato long time measurement project that shows the impact of Carbamidenitrogen to the pH when using RO water in comparison to your other fully-passive Kratki tomato that I assume was fed only Nitrate and Ammonium. I am suggesting this, because many people use those „made for hard tapwater“ liquid fertilizers in (semi-)hydroponic RO setups and end up with epic battles against acid drops fighting them back with sorts of rehardening materials like eggshells or by adding pH buffers. And could you please consider buying a professional glue gun before building another Kratki? 😉
- Could you describe a way to create your own liquid (single, two part, three part) fertilizer from liquid mono-fertilizers at the example of „canna mono“ products, taking the limited information into account endusers usually have about those products. I am asking this, because most people have easy access to liquid mono-fertilizers, but not to the salts, or they can not afford the overhead costs of their own production. Maybe, if you like the idea of a wider spec. (semi-professionals or enthusiasts) of people using Hydrobuddy, this could become an additional calculation mode.
I hope my questions and suggestions are not too basic or of the „you would not do it this way“-type or from the unprofessional side. Otherwise I would be more than happy for hints and keywords about how or where to find information to answer the questions myself.
✌🏻
Thanks for taking the time to comment and make suggestions! I'll certainly keep these ideas in mind for videos during the next few months.
I really feel like I'm going to have a completely different yield after watching your video. So thank you for providing your knowledge to the community. I would like to ask: When using soil, would you still want to use the run off to measure output pH & EC, or would you recommend performing a slurry test with the soil closes to the root environment? Thank you for your time.
Thanks for commenting! I'm glad you enjoy the content. When using a soil you still want to perform an EC measurement of the runoff. However, the soil - depending on how it's amended - can contribute a lot of substances that do not register in an EC measurement because they are not ionic in nature (like sugars for example), so the runoff of a soil can be at equivalent osmotic pressure at a lower EC.