Hi guys, I have a large grow cabinet with a 16 site reservoir DWC and top feed system. I’ve successfully grown soil pots in this cabinet with a kind LED light system, but I haven’t been able to get the DWC down as far as nutrient numbers and how to properly drain and replenish nutrients. I’ve had several successful crops but they haven’t been at maximum potential. I have one going now that’s about ready but I ended up over feeding week 5/6 and it fried the leaf tips and 3/4 out of 13 have small horn like extensions from their colas with white pistils where all of the plants have already shifted to orange. What does this mean? Can someone help with some questions I have on getting it right the next time?
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Foxtails buddy! Nothing to be worried about, extra bud! 
It’s really no problem but it does indicate a less than optimal situation since it is a STRESS reaction. You hear me coming…there are MANY potential causes for this… Luckily there are 3 primary ones and usually it’s one of those… heat stress, light stress and genetics.
Heat stress: growing in +80 df could potentially be the cause.
Light stress: High ppfd outputs without CO2 supplementation is another one.
Flowering too long, usually under too intense light is a frequent cause and maybe this is the case with you? It’s a good idea to gradually build up light intensity during flowering but also to dial it back down the last couple of weeks towards harvest.
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That over feeding could very well have induced it as well btw. That’s stress too.
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Oh man, thanks! I have 2 6 inch fans at the top but I got a larger light than what was supposed to come with cabinet and I was worried I had it too close.it’s a kind xl600 I don’t have the timing right so they grow too tall, this time I did 2 weeks veg before flower. The seeds were feminized from a reputable dealer. My main question is I’m using lotus nutrients and I stick to the schedule but my numbers are always off EC and PPM to what it should be. I’ve been using purified water but I don’t know how much to fill up the reservoir ideally. How often and do I completely replace the water? I’m feeding 4x a day on the top feed every 6 hrs for 15 minutes. Is that too much or even necessary?
I’m sorry to hit you with all these questions but I very much appreciate your help!
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Every fortnight.
It’s a good idea to start with cutting whatever the fabricant says you should feed in half. They want you to use as much as possible of course and usually a lot less is already fine or even better. Cut it in half and see where it gets you, then build up?
Sounds like a lot?
I am absolutely no DWC expert but I’d just keep my EC & pH values in the tank in check. You shouldn’t be going over an EC of 2.0 I reckon. Usually 1.5 or so should be enough. I’d start at 1.2 or so and build up. 
Absolutely no problem. It’s what this family is for.
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@donv Hiya 
What are your root zone temps?
What kind of H2O are you using?
What have your ppms been running?
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What scale? I prefer EC!
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You would ya Nerd.
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Holy smokes, thank you thank you thank you! Can you recommend growers or sites that can easily explain at what time and how to bend and top and manipulate for maximum bud production?
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Just doesn’t make sense to me. One is using the 500 scale, another the 700. Overcomplicating sh*t. Just use EC 
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I like that it makes sense to somebody. It gives me hope.
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I was going by a pre printed feed schedule by Lotus when I started but I realized the online recommended feed schedule for DWC was different. Week 5/6 I didn’t change the water correctly. Right now week 8 it’s 2.2 and 1100
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By root zone do you mean the water temp it’s 68 degrees F or the air between the water and the baskets? I use purified bottled water when I change it.
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Sure, a lot of the growers on here can and I’m sure they will chip in. I won’t right now, bit much to get into as I’m about to leave the house. There’s a lot of good videos on youtube about topping and supercropping too (including the legendary kushman video). 
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What did the foxtail say…
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This man right here is your RDWC expert by the way @donv, he runs an rdwc comm. grow op! Didn’t you keep around 1.8 EC @Slym3r?
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Week 8 a 2.2/1100 is pretty high. What is the level of the bottled water you are using?
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0.1 and 32
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I LOVE a good mystery! We are gonna figure this one out.
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Hi @Slym3r is the Kind xl600 too big and do I have it too close? How much water is ideal to start with? Should it reach the bottom of the net cups?
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