I have a few questions for you. =o) I'm starting my first grow. I have a 4 x4 tent, 400 watt hps and a400 watt mh. Right now I'm just running t5s until I sex my seeds. They are about an inch tall right now. Is it too early to 12/12 them? When do I add the nutrients? I'm going to use ionic bloom & grow. My seeds are g13 pineapple express, blueberry gum, and kardy kush. Have you ever tried liquid co2? I have a bottle from aquarium pharmaceuticals called co2 boost. Would you try it? If so when would be a good time to add it? I don't have aco2 system and wasn't planning on adding one. Do you think the liquid would help or hurt? I'm sure I'll have more questions but those are the most important ones right now. Thanks.... Oh and this is a hydro setup..
You can start running a few hundred uS/cm around 10 days from being above ground. They will let you know when they need them, but somewhere in 7 to 10 days from hatching they'll start begging for food. Be sure to pre-treat your rockwool properly.
You can also begin 12/12 lighting whenever you like. I prefer to let them go for 2-3 weeks before flipping.
I have never tried "Liquid CO2" and I think it will probably do more harm than good. Focus on the basics. The temperature/humidity, pH, and nutrient levels are going to make a much larger difference than some magic bottle of CO2.
Yes - I know the UTFSE.. but the info overload makes it simpler to ask (even if asked before).. with an auto-strain you can run 24/0 if you want - or so all says.. but if you were to run on 18/8 or 20/4.. how careful do you need to be with "darkness"? As always trying to minimize males.. normal strains are easy to stress up.. but do I need complete darkness if lamp is off? Is a normal room "by night" to bright? Or in that case - better run 24/0 ?
I have not grown an Auto strain before so I couldn't tell you. Maybe someone else can, but you might need to go figure this out.
I think, when in doubt, just do it right and get it totally dark and run a 18/6 or 20/4 light schedule to give the plants some time to recover. I find that 18/6 lighting and 24/0 lighting grow the same sized plants but one of them uses 25% less energy. Dark periods are important indoors, it isn't like outside with the moon, you usually need it dark to keep the plants from stressing.
You look like you might be over feeding some nutrients and under feeding others.
Watch your Nitrogen level. It could be the kind of nitrogen you have in your system but that is definitely something to keep you eye on.
The element in short supply looks to be Potassium, and possibly magnesium. This could be a temperature thing, so if your temps are ever over 80 degrees that is a possibility rather than the Potassium shortage. You definitely have some of the early signs of Nutrient Toxicity.
Deep, dark, lush growth that is so green it is nearly blue indicates a phosphorus lockout. The burned tips indicate heat damage, potassium deficiency, or salt-buildup. The interveinal chlorisis (the yellowing between the veins) indicates a mobile element deficiency, usually Magnesium.
My suggestion to you is to rinse the media with a balanced nutrient profile, including nitrogen, phosphorus, potassium, and calcium all at about the same level, and magnesium at about 1/2 the level of those. Effectively a 1-1-1 with a 1% calcium and 0.5% magnesium. Let me know what nutrients you have and I can tailor something for you to fit this. You want this solution to be about 250 to 350ppm (0.5ec to 0.7ec) and you want to pH balance it for you respective media (5.8 for coco/peat, 6.5 for soil). Then you run 2 to 3 times the volume of water to the volume of media. A 3 gallon planter would need 9 gallons of solution.
Then you'll let it rest for 3 to 5 days (or until they are about 80% of the weight they were when saturated) and by then you should be seeing some yellowing on the lowest leaves (the single and triple bladed ones that are way down by the dirt). This will indicate your plant has recovered and is consuming reserve nutrition to produce healthy new growth. Once you begin to see this happen then you can feed the media again, replenish the microbes and organics, and keep an eye on the nutrient levels from here on out.
You might also have a water problem to investigate. Hard water, of a high starting ppm, can cause the problem you are seeing. The extra calcium and sodium already present in the tap water builds up over time, and the cations then interact with your ionic salts and precipitate in the media. They also force other cations, like magnesium and potassium, to compete (electrically) for absorption by the root system.
However you carve it there is most definitely a little build up and a chemical imbalance that is kicking in. Clean the media and rebuild your organics. Watch your calcium and sodium in your tap water, filter it if you have to.