This is my first time trying hydro. Photo seeds started in rapid rooters. Going on 3 weeks. In a 4x4 with a 200 watt 20" away.
Older leaves are turning yellowish and some seem burnt at the very tip. Any help would be appreciated.
Ppm around 300 and ph around 5.9. During the day its kept around 75⁰ and 70% humidity
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Not an expert so id wait for the pros on this, but if it was my plant id feed it and add a bit more nitrogen than its been getting
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Welcome @xGibson70 to the forum. Is the water level touching the roots? Until they get to going you’ll need to keep the water level higher that recommended. I like to put a couple air source in my buckets. One in the water level hose and a bubbler. Make sure they’re getting intake for fresh air and a tent fan to circulate air. You should getting a bit more ppd at this stage. I use the 300 ppd for my rapid rooter then up it to 600 by the first week in the bucket.
All plants will vary though. One of mine was a late grower but was a beauty at finish.
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Bump that up to 800 Growmie 
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Make sure the roots aren’t rot, especially if no aeration. Is water temp too hot?
like the Gromie above said. Bump that ppm up.
The light’s instructions may have suggested heights for each stage
A question. Is that girl already stretching for light?
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Water temp is 68-70. I didnt think they were stretching for light. The photone app says theyre getting around 300ppfd.
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The water goes up about an inch above the bottom of the basket. There’s roots starting to come through. I have been confused about the water level tho, i was trying to keep it right around the bottom of the rapid rooter.
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I have a different set up but I can push down on my clay and water appears. Would that be the same in this set up?
Once the roots reach to the water you’ll see rapid growth.
Once the roots touch the water start letting the water level drop and the roots will follow the water. By leaving a gap between the water and the basket will allow a bit more O2 in the system. By you need the bubblers and I used a product called Hydroguard which is beneficial microbes to colonize your root zone. These microbes will help stabilize the water so bad microbes can’t get to y ph r roots. Plus they will break down sugars and other salts that tend to build up in the buckets.
If you suspending your plant in clay pebbles over water then you are using DWC hydroponics and yes it is the same.
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Thanks for all the info!
I have a 15/L air pump and a stone in each bucket. I think there’s enough bubbles.
Im also using king crab by roots for success. Is that the same as Hydrogaurd?
Roots are starting to poke out of the basket, ill try lowering the water level. Should i be using any foliar spray or watering from the top at all?
Thanks again for all the help
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Yes that will do the trick. I also add a little RapidStart from General Hydroponics to give the root a start during seedling stage. Roots and airflow all the way through your grow.
Yes I do the top feeding until they take off. I would worry too much about foiler spray unless you’re having an issue. With hydroponics they get plenty of water. Just make sure they get just enough light and airflow. Although we are added nutrients to the bucket they actually get the building blocks of life, carbon, from the CO2 in the air. The nutrients power the energy and water powers the absorption. So keep an eye on VPD for each stage.
Harley is the hydro man for knowledge.
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Another tip that I use for my indoor tent is I have a LED UV Bug zapper that kills bugs and can help control mold spores as well.
I purchased this one from Amazon and just purchased another as it does an excellent job.
And it’s on sale for $26 I’ve been wait a few months for them to get back in stock.
Ultraviolet (UV) radiation from UV lamps can indeed play a role in dealing with mold. Here’s what you need to know:
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UVGI Cleaners: If properly designed, ultraviolet germicidal irradiation (UVGI) cleaners that use UV lamps may destroy indoor biological pollutants such as viruses, bacteria, and some molds. These cleaners are effective on moist surfaces within HVAC systems (like cooling coils, drain pans, or ductwork). However, typical UVGI cleaners used in homes have limited effectiveness in killing bacteria and molds. To effectively destroy most mold spores, higher UV exposure than what home units provide is necessary. Additionally, even dead mold spores can still cause allergic reactions, so UVGI cleaners may not significantly reduce allergy and asthma symptoms¹.
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UV Light and Mold: UV light, similar to sunlight, can kill mold and other bacteria by penetrating the organism’s cells and damaging their DNA. Once a mold spore’s DNA is damaged, it can no longer reproduce. So instead of spreading, the mold cell eventually dies³.
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Airborne Mold Spores: Ultraviolet light won’t just kill mold on surfaces; it can also target mold spores floating in the air. Mold spores are like the reproductive units (similar to seeds) of the fungus, and inhaling them can be allergenic and toxic to humans².
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Caveats: While UV light can indeed kill mold spores, it’s not as simple as zapping a moldy wall with a UV lamp. Most household UV lamps don’t generate enough exposure to effectively kill mold. Additionally, dead mold spores can still aggravate allergies and asthma⁴.
In summary, UV light can be part of a mold control strategy, but it’s essential to consider other methods as well for comprehensive mold prevention and removal.
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Thanks, i just ordered one. Do you think it could be mold spores on the tips of the leaves? Ive been keeping the inline fan running all day and they have two oscilating fans. Vpd stays under 0.8
They look better color wise today. I raised the ppm to 600 yesterday and it went down to 550 so i assume theyre eating.
Could be a number of things. I’m thinking lack of nutrients.
The first set of leaves on cannabis seedlings, also known as cotyledon leaves, can turn brown due to various factors. Let’s explore some common reasons:
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Overwatering or Underwatering: Incorrect watering practices can stress seedlings. Overwatering leads to root rot and insufficient oxygen, while underwatering causes dehydration and nutrient imbalances. Ensure the soil is slightly damp but not waterlogged.
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Nutrient Deficiencies: Lack of essential minerals like nitrogen, potassium, or calcium can cause brown spots on leaves. Nutrient deficiencies affect different parts of the leaf, resulting in discoloration.
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Improper Soil Type: Using the wrong soil mix can hinder seedling growth. Ensure your soil provides adequate drainage and nutrients.
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Unsterile Equipment: Contaminated tools or containers can introduce harmful pathogens, leading to damping off (rapid seedling death).
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Lack of Ventilation: Poor air circulation can contribute to fungal diseases. Ensure proper ventilation around your seedlings.
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Soggy Soil: Excess moisture can suffocate roots and promote fungal growth. Allow the soil to dry out slightly between waterings.
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Watering from the Top: Watering directly onto the seedlings can damage delicate leaves. Water at the base to avoid wetting the foliage.
Remember that seedlings are fragile, so maintaining optimal conditions—proper moisture, light, and ventilation—is crucial for their healthy development. If you notice brown leaves, assess these factors and adjust accordingly. 
What are you feeding them?
When it comes to DWC (Deep Water Culture) cannabis plants, brown leaves can be a sign of underlying issues. Let’s explore some possible reasons for brown leaves in DWC setups:
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Root Health and Water Conditions:
- Brown Filament on Roots: The brown filament you’re observing could be due to nutrient buildup or early signs of root rot. Ensure your water temperature remains consistent (you’re doing well at 68°F) and maintain proper oxygen levels for the roots.
- Water Level: Keep the water level an inch below the net cups to prevent over-saturation of the roots.
- Nutrient Strength: Consider adjusting your nutrient strength. Since you’re using the Lucas formula nutes, monitor the ppm (parts per million) carefully. Lowering it to around 400 ppm or less might help.
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Nutrient Imbalance:
- Organic Nutrients: Bio Thrive (General Hydroponics) is an organic nutrient line. While it works well in soil, it might not be ideal for DWC. Organic nutrients can sometimes cause issues in hydroponic systems. Consider switching to a hydro-specific nutrient line.
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Environmental Factors:
- Room Temperature: Your grow room occasionally reaching 85-90°F could stress the plants. Try to maintain a more consistent temperature range.
- Air Circulation: Ensure good air circulation to prevent stagnant air around the roots.
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Preventive Measures:
- Aerated Worm Casting Tea: Consider adding an aerated worm casting tea to prevent and treat root rot. It can be effective in non-recirculating DWC systems.
Remember that DWC requires close monitoring, especially during the early stages. Adjusting nutrient levels, maintaining optimal water conditions, and addressing any signs of stress promptly will help your cannabis seedlings thrive. 
I’m using GH Flora line nutrients with a feed chart for mixing them for each growth stage.
See if they have a feed chart for you to use. I would make sure to use the Richmond Hydroponics 2 part Bloom when you switch to a 12 x 12 photoperiod.
Ive heard that the Flora line is really good. I tried the richmond nutes because of how simple it seems. 2 part veg and bloom. Supposed to be no need for calmag or other supplements. Ill probably just get something to flush.
If this stuff doesnt work out ill definitely try Flora next time
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I bet it is good. I try to find a feed chart maybe. But probably just continue the grow until it’s time to flip the lights for flower. Then you should use the flower 2 part they have.
