5x5 LED - T-Time grow time

Discussion in 'LED and other Lighting' started by T-Time, Sep 25, 2017.

    Prawn Connery

    Prawn Connery Well-Known Member

    Soilless, by its definition, is not hydro - because the substrate provides nutrient.

    I define coco as hydro - en evthough it is not an entirely inert substrate.

    I'm sorry, but by your definition, every time you water soil plants with a nutrient solution, it's "hydro". I think we both know it's not ;)

    And for the record, plant pathogens such as pythium are in most water sources and spores are easily carried by wind and insects, meaning it is virtually ubiquitous. Plant roots have natural defences against root rot, only allowing it to take hold when they start to die or stress in anerobic conditions, and when temperatures are conducive to rapid multiplication of the pathogen, which start to colonise the roots in large numbers and enter the plant through damaged tissue.

    Which all means it's pretty much everywhere (except in the most sterile environments) and will attack the plant only when conditions are right.
    Last edited: Oct 20, 2017

    ttystikk Well-Known Member

    This is a basic textbook definition.
    Prawn Connery

    Prawn Connery Well-Known Member

    Is there another definition?

    ttystikk Well-Known Member

    No. The point is that hydroponic nutrients must already be water soluble, where nutrients in the soil needn't be.

    The plant cannot take up nutrients until they're water soluble. Hydroponic nutrients, by definition, already are. Soil based nutrients may need to be broken down by chemical or biological processes to become water soluble and thus available.

    Therefore the substrate for hydroponics can be anything that doesn't offer the plants a significant portion of their nutritional needs. Some of these include sand, rockwool, coco, nothing (like RDWC), expanded clay pebbles, stones, peat, perlite, etc.

    This also means that if the nutes are water soluble, then they can be carried in the water by any system that delivers water to plants.

    Specific examples;
    Calcium nitrate is water soluble and can therefore be used as a hydroponic nutrient.

    Epsom salt, aka magnesium sulfate, is also water soluble (the word 'salt' is the giveaway).

    Calcium sulfate, which is what you get if you mix the above two improperly, is 97% water INsoluble and is therefore not a hydroponic nutrient, although it's a great organic soil amendment. It's also known as gypsum or drywall.
    Last edited: Oct 21, 2017

    T-Time Well-Known Member

    8 days after the flip to 12/12
    Still waiting for the white pistils to show up:sleep:
    Aaaaagrrrr why it has to take so long every time... Since the switch to SIP I'm only opening the tent to see whats going on. Don't have to water every other day. Heck I don't have to water for nearly two weeks. Not sure it's a good thing or not :lol:

    Did anyone ever used those aquarium oxygen test strips ? I'm thinking to give them a try and see how they work and how much oxygen is in my tank now, given I don't want to spend over 200 bucks for a DO meter.
    Also, anybody has any idea how long does the water stay saturated with oxygen after the pumps stop?

    Anywas, couple snaps from today.
    20171022_133946.jpg 20171022_133938.jpg 20171022_134207.jpg 20171022_134045.jpg 20171022_133855.jpg
    Prawn Connery

    Prawn Connery Well-Known Member

    Hey mate, I'm not sure if it's an illusion of the lighting, but the lower leaves look a bit yellower than the new growth, and your PPM is quite low, so I'm wondering if you need to up the nutes a little? Absolutely no signs of nutrient stress, and your plants will need a bit of boost during the first couple of weeks of flower during the stretch period.

    With the DO, you're roots will tell you. They should be a nice white to creamy colour with lots of fine root hairs off the main roots. When they're starving of oxygen, those fine root hairs are the first to die off and the roots start to go a little off colour. You'll also start to smell it - they won't have that nice fresh vegetable smell - while growth will start to slow.

    If you've got a little aquarium air pump and are worried about noise, just turn it down a bit until you can hardly hear it (assuming it's an adjustable pump). Also, bigger airstones can help, as they spread the bubbles so you don't get a concentration of bubbling in one spot, which can add to noise.
    Prawn Connery

    Prawn Connery Well-Known Member

    No argument there, but for the reasons you've pointed out, you can't take substrate out of the equation, as it certainly can affect nutrient availability through cation exchange and pH range - in effect, drawing or releasing nutrient ions suspended in water depending on the media and acidity/alkalinity. The same applies to organic chelation in organic hydroponic systems.

    So really, unless you are running a completely sterile DWC, NFT or aeroponic system with no substrate at all (and that includes rockwool, expanded clay et al), it is not a pure hydroponic system according to your definition. The reality, however, is that most growers do use a substrate - even a small amount - to stabilise their plants, but the hydroponic principles still apply, in that nearly all the nutrient is supplied to the roots through dissolution (even in organic systems).

    Which is why I include coco in hydroponics and not soilless.

    wietefras Well-Known Member

    I have one of those expensive DO meters and I'm ashamed to say that I have never gotten around to measuring the DO with the plants in full flower. Should find the damned thing again and at least try it this time around :)

    I've had plants for a month in still water though and they did just fine. No bubbles at all. Just some periodic filling up of the bucket obviously, which would have introduced some DO, but there was no air pump or circulation pump. The water started to smell somewhat, but the roots were white and plants looked fine.
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    ttystikk Well-Known Member

    I hear you, but;

    The effects of substrate are unrelated to whether the system is delivering nutrients via the water and is therefore a hydroponic system.

    Definitions exist for a reason. That reason is mutual understanding. If you and everyone else makes up their own definitions of concepts, then how would anyone ever understand one another? Should I start calling apples walnuts just because they both grow on trees?

    The cannabis industry already has a very serious terminology problem, aided and abetted by companies and distributors who are deliberately trying to mislead their mostly uneducated customer base about basic plant nutrition, specifically in order to overcharge them by as much as 100 times for basic nutrients. Otherwise, Advanced Nutrients could never sell a quart bottle with a dollar's worth of epsom salt for $100!

    I'm not picking on you. You're a sharp dude. The point I'm making is that it's important to use the basic glossary terms of our profession correctly in order to be understood- and to be taken seriously by others who do.
    Last edited: Oct 23, 2017
    Prawn Connery

    Prawn Connery Well-Known Member

    I honestly think we're talking about the same thing. My original point was to differentiate between coco as a hydroponic medium (even though it is not a completely inert substrate and has a relatively high cation exchange capacity compared to other traditional hydro media) and as a soilless (organic) medium.

    There is already confusion in some minds about this, so I often clarify the reasons why I prefer it as a hydroponic medium: namely that it has most of the advantages of accelerated-growth hydroponics (soluble nutrient delivered direct to the root zone) with some of the advantages of a good soil/soilless media (moisture-retention, stability, some nutrient and pH buffering, and good drainage/aeration). It's also a renewable resource that can be recycled in the garden.

    There's a lot to like about it. :mrgreen:
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    Prawn Connery

    Prawn Connery Well-Known Member

    Oh, and I forgot to mention, run-to-waste coco is also kick-arse when it comes to growing in hot climates.
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    T-Time Well-Known Member

    I think it started flowering today :weed: Thats 10 days after the flip.
    20171025_194540.jpg 20171025_194639.jpg
    Did some small defoliatio today. I could probably do some more, but am always afraid to do so :P

    Before: 20171025_185900.jpg 20171025_185905.jpg

    And after. 20171025_194320.jpg 20171025_194328.jpg 20171025_194333.jpg 20171025_194346.jpg

    Need to take more training classes :/

    Bumped the light to 700W as its cold in the tent (24*C). Doesn't look like ladies are complaining :)
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    vidrose Member

    Hey T-Time, do you have a closed loop system for led cooling or a reservoir? Ive got a 15-20 gallon reservoir set up, it heats up to around 90f in the tank and around 100F at the cob cooling blocks. Cobs at 49.9v 5.2 amps draw, 8 cobs total. I think ill be needing a cooler like you have once i pump them up.
    I like your set up btw, nice job.

    T-Time Well-Known Member

    Theres a 42L (11 gallon ) res in there cooling 20 cobs set ap at around 35W each. This cooler is pretty effective as as its cooled the inline fan thats used anyways and the pump that circulates the water is 12W only.
    Water behind cobs stay at nice and cool 22*C (71.5*F). Have any photos of Your setup ?
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    ttystikk Well-Known Member

    How many watts are driving those chips? Is that the cooling res temp at lights on, or at lights off? Unless there's a heat sink in the system somewhere, those two temperatures will vary.

    Randomblame Well-Known Member

    Good morning, or should I better say, good night?
    Theres a 42L (11 gallon ) res in there cooling 20 cobs set ap at around ... "35W each"...

    And yes, there is radiator inside the housing mounted behind his inline fan, pictures are in his opening post/1. page I believe.
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    T-Time Well-Known Member

    35w on each cob, 700w total. Temps are measured at light on with laser gun right behind at rhe bar where the cob is mounted. Not sure how accurate are the measurements tho. I have to measure the res temp.
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    Randomblame Well-Known Member

    Nice setup!
    Is all the exhaust air completely pressed through the radiator or is he only "hanging" in the airflow?

    And a quick tipp!
    Put a small piece of black electr. tape on the meassuring point, metallic surfaces tends to falsify the readings.
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    T-Time Well-Known Member

    Radiator is fully enclosed. I picked a bigger rad so it wouldn't restrict the airflow. It's about 1.5-2 times bigger then the 150mm ducting.

    I did couple measurements w/ the tape (thanks for the tipp) and w/o. The tape didn't change much. The temp in the res stays at about 27*C so i would say 3mm of alu falsify the readings.
    20171031_154406.jpg 20171031_155407.jpg 20171031_154710.jpg

    Did another defoliation session yesterday. Ladies lost about same amount of leaves as last time and still looking happy.

    Temp in the tent is at the low side @23*C
    Slightly bumped PPM to 1500 and PH is @5.93
    Don't have much to do at this stage. Pluck the leaves every week and top up the res every 12-14 days. I don't think they will fully fill the vertical space.

    Few photos from today. I'm not the best photographer :P

    20171031_154814.jpg 20171031_154840.jpg 20171031_154829.jpg 20171031_161415.jpg 20171031_161454.jpg 20171031_155157.jpg

    ttystikk Well-Known Member

    Just for fun, check res temp at lights off.

    Is the res open? Do you have to add water occasionally?

    I'm just curious about where the heat is going.

    Don't get me wrong, my interest isn't in being critical. Your system works! I'm interested in how and why, is all.

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