Light rays breakdown
https://www.facebook.com/watch/?v=2745261152532559
Light burn and excessive heat
https://www.facebook.com/groups/738719191196990/permalink/1398783151857254/?app=fbl
Blue and Red Lighting
In a grow light, blue light primarily promotes vegetative growth, encouraging healthy leaf and stem development. It is particularly beneficial for seedlings and young plants as it helps them develop compact, strong structures. Blue light also helps regulate plant shape and increases the opening of stomata, which allows for greater carbon dioxide uptake, boosting overall metabolism.
Role of blue light
Promotes vegetative growth: Blue light is essential for the early, leafy growth phase of a plant.
Develops strong stems and roots: It helps create sturdy, strong stems and healthy roots, creating a solid foundation for the plant.
Encourages compact growth: Blue light can inhibit stem elongation, leading to shorter, more compact plants with dense foliage.
Aids photosynthesis: It helps in the production of chlorophyll and the opening of stomata, which are crucial for the process of photosynthesis.
Boosts metabolism: By increasing carbon dioxide intake through open stomata, blue light speeds up a plant's metabolic processes.
How to use blue light effectively
Combine with red light: For the most comprehensive growth, blue light should be used in combination with red light, which is more important for flowering and fruiting. Many growers use a full-spectrum light to ensure a balance.
Adjust for different stages: Use a blue-heavy spectrum for the vegetative stage to build a strong plant structure.
Consider end-of-cycle use: Some growers may use a blue-dominant spectrum at the end of the flowering cycle to potentially enhance color and potency by increasing anthocyanins.
A combination of both red and blue light is best for growing hydroponic carrots, as blue light promotes healthy root and vegetative growth, while red light is highly efficient for photosynthesis and can influence overall biomass
. For the root development stage, a higher proportion of blue light is beneficial, and for increasing yield, red light is crucial, making a full-spectrum light with both colors optimal for the entire growth cycle.
Blue light benefits
Promotes strong root growth: Blue light is crucial for developing a strong root system, especially in the early, vegetative stages.
Increases photosynthesis: It enhances photosynthesis, leading to the production of larger, greener leaves.
Boosts antioxidants: Studies show blue light can lead to higher total phenolic content, especially in the outer layers of the carrot root.
Red light benefits
Essential for photosynthesis: Red light, with wavelengths around
A good light will cover:
Broad-Spectrum for Balanced Plant Growth
Our grow lights are designed to be well-rounded, supporting both vegetative growth and flowering/fruiting, making them a great all-in-one solution for a wide range of houseplants. While higher colour temperatures like 5000–7000K are often recommended for leafy greens such as lettuce, a 3500K spectrum offers a good balance across the PAR (Photosynthetically Active Radiation) range, covering both blue and red wavelengths. This makes it ideal for not only foliage but also promoting blooming in flowering plants.
Home-Friendly Aesthetic
Another key reason we chose 3500K is because of its warm, natural white tone, which blends beautifully into living spaces without the harsh clinical feel of colder, bluish lights. It’s a great choice for those who want both function and style.
Goseneck Stability
Regarding the gooseneck, we completely understand the concern! We upgraded our goosenecks about a year ago—they’re now reinforced and strong enough to hold the lights firmly in any orientation, not just vertically. Whether you’re side-mounting or angling them toward hanging baskets, they’ll stay put.
LED color temperature, measured in Kelvin (K), describes the light's color appearance, from warm (yellow/red, ~2700K) to cool (blue/white, ~6500K), with lower K values being warmer and higher K values cooler, affecting mood, visual acuity, and suitability for tasks like cozy living spaces (warm) or high-focus work (cool). The actual spectrum involves coating blue LEDs with phosphor, so warmer lights have more phosphor and cooler ones less, creating different color profiles.
Common LED Color Temperatures & Uses:
Warm White (2700K - 3000K): Yellowish, cozy glow, like traditional incandescent bulbs; ideal for living rooms, bedrooms, hospitality.
Soft/Neutral White (3000K - 4000K): Brighter white with slight yellow, good for kitchens, offices, commercial spaces.
Cool White/Daylight (4000K - 5000K): Bright, crisp white, mimicking natural daylight; great for retail, warehouses, tasks needing focus.
Daylight/Bluish White (5000K - 6500K+): Very bright, bluish; used in hospitals, labs, factories, agriculture for maximum concentration.
Key Concepts:
Kelvin (K): The unit of measurement for color temperature; lower K = warmer, higher K = cooler.
Spectrum: LEDs start as blue; warmer tones are achieved by adding phosphor to filter the blue light into warmer hues, affecting the overall spectral output.
Mood & Function: Warm light promotes relaxation, while cool light enhances alertness and detail perception.
Circadian Rhythm: Very cool lights (above 5700K) can disrupt sleep, so warmer tones are often preferred for home use.
Lumens and Kevin's and Flux
https://www.paclights.com/explore/5000k-lumen-in-lux-lighting-explained/#:~:text=The%20Role%20of%20Color%20Temperature,clarity%20and%20focus%20are%20paramount
Hydroponic radishes thrive with full-spectrum light in the range of 5,000 to 7,000 Kelvin (K), with an intensity of approximately 5,000 to 10,000 lux. This mimics the conditions of natural daylight and supports strong vegetative and root growth.
Kelvin (Color Temperature)
Optimal Range: 5,000K to 7,000K.
Effect: Lights in this "cool" or "daylight" range are blue-heavy, which encourages robust leaf and stem development, essential for the overall health of the radish plant before the root develops.
Recommendation: A full-spectrum white LED or fluorescent light in the 6,500K range is excellent for all stages of growth, especially the vegetative phase.
Lux (Light Intensity)
Optimal Range: 5,000 to 10,000 lux during the plant's main growth period.
Seedling Stage: Young seedlings benefit from slightly lower intensity, around 5,000 to 7,000 lux.
Mature Growth: As the plants mature and the radish bulb forms, increasing the light intensity towards the higher end of the range (or even up to 20,000 lux) helps maximize yields.
Note: Lux is a measure of light visible to the human eye. A more precise measure for plants is PPFD (Photosynthetic Photon Flux Density), which should ideally be around 400–600 µmol/m²/s for the vegetative stage.
Lighting Schedule
Radishes need a consistent light cycle to thrive. Provide a minimum of 6 hours of light per day, but 8 to 10 hours or an 18-hour-on/6-hour-off cycle is ideal for robust growth. Use a timer to maintain a consistent schedule and mimic natural day-night fluctuations.
Sent from Outlook for Android
From: Harun Kennedy
Sent: Tuesday, December 30, 2025 11:52:20 AM
To: Harun Kennedy
Subject: Kelvin versus molar flux density
The value
8-15 mol/m²/day cannot be expressed in kelvin because they measure fundamentally different physical quantities.
Explanation
The unit
mol/m2/daymol/m squared / day
mol/m2/day represents a molar flux density, which describes the rate at which moles of a substance pass through a specific area. The kelvin (
KK
K) is the unit of thermodynamic temperature, which measures the degree of hotness or coldness of an object. As these units correspond to different physical dimensions (flux versus temperature), a direct conversion between them is not physically possible.
For optimal growth, hydroponic lettuce needs LED lights with a color temperature between 5000K and 6500K (cool white/daylight spectrum), as this range is rich in blue light which promotes compact, bushy vegetative growth.
Key Lighting Requirements
Color Temperature (Kelvin): Aim for lights in the 5000K to 6500K range. This "daylight" or "cool white" spectrum encourages vegetative growth and prevents the plants from becoming leggy (stretching for light).
Light Intensity (PPFD/DLI): Plants require light intensity to be measured in Photosynthetically Active Radiation (PAR) or Daily Light Integral (DLI), as lumens and lux are measurements for the human eye and are less reliable for plants.
Intensity (PPFD): The optimal intensity is around 200 to 400 µmol/m²/s (micromoles per square meter per second).
Daily Light Integral (DLI): The target DLI is generally between 12 and 17 mol/m²/day.
Light Duration (Photoperiod): Provide 12 to 16 hours of light per day, followed by a dark period. A common effective cycle is 16 hours on and 8 hours off.
Distance: LED lights can be placed relatively close to the plants (typically 4-12 inches) without burning them due to less radiant heat compared to other types of grow lights. Adjust the height to achieve the target light intensity and prevent the leaves from curling or scorching.
By using lights in the recommended Kelvin range and ensuring sufficient intensity, you can achieve healthy, vigorous hydroponic lettuce growth.
If growing preparation is done reasonably well, different plants will be emerging and flowering at a great rate and maintaining them and the space around your containers will be a job. Plants nutrient deficiency starts to show where the nutrient reservoir mix falls below a certain level, and must be maintained to a higher level. The range of plants can become a fun thing rather than a sustenance necessity. Finding the balance between need and desirable fun needs to be met. In turn the different grow rates, and general appearance and a shear mass forming, that either don't get utilised (eaten) and become a pest magnet, is a factor to take into account, certainly when space for growing is at a premium.
Knowing when to clear is important, but in some cases allowing the plant to flower in adequate sunlight and warmth conditions, can lead to the developing of seeds for future use (after putting the flowers in a bucket, letting them dry out and taking the seeds...) of course this depends on the given variety of plant.
General pointers
Let me add some of my experience.
Specifically height and spacing requirements for plants.
I started like you. With a wire rack. Some shoe totes as my containers. Spacing was 3 inches between plants. Not good. Is choked out light from the slower growing plants.
I have found. 6 to 9 inches between holes is good spacing for most lettuces and leafy greens Ive grown. 10 to 12 inches is ideal in my opinion.
Now as your rack is set up now. All those shelves could be used as a germination station. Dont need much height (or spacing at this point)
From top of contaner to top of where lights are hung at its highest. Shoot for 18 inches. This gives plenty of room.
Basically. Your shelf. Can utilize 2 shelves for sure. Would be pushing it for 3 of them. But with the right lettuces. You could do it.
As for containers. I've done totes of a couple different sizes. But I suggest, getting as close to an nft rails/channels (or get the actual rails from cropking) I found this worked best, as you can get. And I could put 2 rails comfortably on each shelf. Or with some modification. You could do 3 rails of nft per shelf. Modifying? Add some wood cross peices, rails set on them.. Have a rail in the middle of the shelf. A rail on the outside back and outside front. If I had a picture I would show you what I did the last time I used this system as Im describing. My build is current bigger now. Not quite finished. But bigger 6 rails wide. Still working in vertical growing. Just bigger set up. Same concept though
Michael Hofius I plan to use 3 shelves with 18 inches of clearance to lights. How much reservoir volume do you suggest?
Mc Yanick depends on what your using. Totes are themselves the resivior. Rails(nft) With a pump set up. Can run comfortable with 5 to 10 gallons. You will add to it every week though. However, the bigger the resivior. The longer it will last. And I usually went 3 weeks. Sometimes longer. But not often. Between nutrient change outs.
This was for 48" nft rails x 6. Three rails per shelf in a 2 shelf set up.
I was gonna buy PVC pipe and connections. DIY it. But after adding up cost. I found that the smaller width 48" nft rails(channels.. I keep saying rails. They're channels) from cropking was cheaper than a full DIY build. And I know for sure they're food safe. Plus the tops come off so easy cleaning. Which is a necessary evil that has to be done from time to time.
Seed sowing and germination
Seed Starting
NFT works so well for leafy Green Vegetables, but one can frow just as well Spring Onions
Pok choi
Kale
Spinach
Lettuce
Mustard Greens
NFT: A pump from the reservoir at the end of a channel pumps water up a pipe and into the top of the channel. The water then creates a very thin film literally just across the surface of the channel. The water then travels back down back into the reservoir washing the nutrient-mix solution across the roots hanging from above. One of the key benefits of NFT is following the seedling stage one doesn't need any form of Grow Support it can simply hang roots into the water film below in the channel.
Plumbing Layer
Types of System
Channel and Pump Cleaning
Turn the taps off of the feeder tubes. This stops the flow from an individual channel. The tubing can then be removed from the individual channels. Lift the whole plastic channel container AMAZON AFFILIATE LINK and clean appropriately. One can do all the steps on individual channels and their feeder tubes without stopping the whole system, by turning off the pump. One can use regular household cleaning agents diluted to no more than 15% of the cleaning solution.. This doesn't have to be inside the channels, more on the surface with a view to clearing as many pests and pathogens. Remember plants in nature existing in regular earthly dirt.
Nutrient Mixing
pH Balance of 6.9 - AMAZON AFFILIATE LINK to Hydroponics pH monitor devices. EC level high after no change for 6 months of 2.34
A hydroponic nutrient solution is a water-based mix containing essential macro and micronutrients like NPK (nitrogen, phosphorus, and potassium), calcium, sulfur, magnesium, and trace elements. You can buy pre-made solutions as liquids or powders or create your own by combining them with purified water. The solution must be carefully balanced for pH and EC (electrical conductivity) to ensure plant health. Key components Macronutrients: The "big three" are nitrogen, phosphorus, and potassium (NPK), which are vital for leaf growth, roots, and overall plant health. Other important macronutrients include calcium, sulfur, and magnesium. Micronutrients: These are needed in smaller amounts but are still critical. They include elements like iron, manganese, zinc, and boron. Base nutrients: You can buy these in liquid or powder form, which are specifically formulated for hydroponics. A common example is a balanced NPK fertilizer like 20-20-20, along with other components like calcium nitrate and Epsom salt (magnesium sulfate). How to create a solution Use purified water: Start with water that has been purified, such as by a reverse osmosis (RO) system, to ensure a clean and predictable starting point. Mix nutrients: Follow the instructions for your chosen pre-made kit or a DIY recipe. For example, a simple DIY recipe might involve mixing a specific amount of a water-soluble NPK fertilizer, calcium nitrate, and Epsom salt into a gallon of water. Check and adjust: After mixing, check the solution's pH and electrical conductivity (EC) levels. The ideal pH is often between \(5.5\) and \(6.0\) for many plants. You may need to add a pH-up or pH-down solution to get it right. Maintenance Regularly add water: The water level in your hydroponic system will decrease due to transpiration and evaporation, so you'll need to add water to maintain the correct level. Perform regular solution changes: It is necessary to completely replace the nutrient solution in your system every one to three weeks, depending on the size and type of system and the growing environment. This prevents a buildup of unused salts and nutrients.
EC, or Electrical Conductivity , in hydroponics is a measurement of the total dissolved salts and minerals (nutrients) in the water solution, indicating its concentration strength. A higher EC means a more concentrated nutrient solution, while a lower EC means the solution is more diluted. Proper EC levels are crucial because too low a concentration can lead to nutrient deficiencies, while too high a concentration can lead to nutrient toxicity and root damage. This video explains the basics of EC and its importance in hydroponics: 40sBright Lane GardensYouTube • 16 Nov 2023
What EC indicates ...Nutrient concentration: EC is an efficient way to gauge the overall strength of the nutrient solution without having to test for each individual nutrient. Plant health: It helps ensure that plants receive the right amount of nutrients for healthy growth without becoming toxic. Plant needs: Ideal EC levels vary depending on the plant type and its stage of growth. Seedlings and leafy greens need a lower EC, while fruiting plants like tomatoes require a higher EC. Why monitoring is essential Too low (< 1.0 mS/cm): The solution is too diluted, and the plant may experience nutrient deficiencies. Too high (> 3.0 mS/cm): The solution is over-fertilized, which can cause nutrient burn, salt toxicity, or prevent the plant from taking up enough water, leading to wilting. Ideal range: A general target for many mature plants is around \(1.8\) mS/cm, but this can vary significantly by crop. This video explains how EC levels affect plant growth:05:15AirgardenYouTube • 9 Dec 2022Measuring and adjusting Use an EC meter: A handheld EC meter is used to measure the electrical conductivity of the nutrient solution. Adjust as needed: If the EC is too high, you can add more water. If it's too low, you can add a concentrated nutrient solution. Monitor regularly: Consistently monitoring the EC allows you to make small adjustments to maintain the ideal level for your plants.
Adjusting flow rate
Types of System
Propogation preparation
The plants don't need any support they can literally be bare roots.
All what has to do is get the plants through the seedling stage to the point they have grown or sprouted roots and can hang over the Nutrient flow film...
Leafy Greens can be grown in Rockwool, Feet pellets, and cotton wool buds to name a few. But as effective as any other cotton wool buds are cheaper than otherwise. After raising the seedlings in a propogation pallete
https://www.youtube.com/watch?v=rB6ULwLNpKA
RED Remo - COCOPEAT METHOD COMPARED https://hyjo.co.uk/blog/how-to-use-coco-peat-in-hydroponics-tips-for-perfect-growth/?srsltid=AfmBOorAHf6i9vuAQxVFmjAHQ0XOCpRaHshrcwwwzuTJBT7DHR5lt3NE
RED Remo BASIC Equipement https://www.youtube.com/watch?v=s8LRc0eF0sc
Key Elements to Dutch Bucket Hydroponics System
These are either Recirculating or Flood and Drain to waste hydroponic system. The bucket itself allows you to supply nutrients top fed via pipes or tubes into a bucket that then collects the nutrients and feeds it back into a pipe either disposing of the nutrient or recirculating the nutrient. So the pipe will either deliver the nutrient back down the channel and into a reservoir where the pump will feed again on a timer or will feed continuously.
Dutch Buckets are so versatile no Grow-Support with a Lid and Net Cup, one can have Coco Perlite, Coco on its own or Hydrogen Clayballs.
Hydrogen Clayballs. As sometimes the shelf life via the Perlite Grow-Supports isn't always so reliable.
Dutch Buckets are limited by shear size and available space to locate them. So for Fruit plants like Tomatoes, Egg Plants and Cucumber and other high value crops and can sit side by side with the Leafy Green vegetables more abundant.