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[cancareent]

Any idea whats going on here? Plants 3/4 feet from light - ph is 6.0-6.3. Temps are 77-80 day 75-78 night. Humidity ranges from 55-70 at different points of the day. They are week 5. Growing in coco, PPM is stable at 850-1000 - 700 chart. Get fed everyday. Anyone have any ideas?

 

[Creeperpark]

When the calcium gets low in the feed water the plant's leaves will bronze. Calcium (Ca[SUP]2[/SUP][SUP]+[/SUP]), is required for structural roles in the cell wall and membranes and is the bones of the plant so to speak. You may not have enough cal-mag in the mix at some point. The bronzing could have happened a week or two ago. A coco grower can help more.

 

[HempKat]

I've never grown in coco so I'm not sure if the ph range to shoot for is that of hydro or that of soil but in either case a ph level of 6.0-6.3 would be a bit low and likely locking out important nutrients. If it should be like soil then at 6.3-6.0 Phosphorus is locked out and so is calcium and magnesium this could appear as a deficiency of those nutrients which could explain what your seeing in the plants. The predominant things being the yellowing of leaves (magnesium deficiency) the bronzing of leaves (phosphorus deficiency) some petioles turning red (phosphorus deficiency) and maybe some leaf tip burning (calcium deficiency) since the picture can't really reveal this to us very easily if you feel you're plants growth is stunted that's also a symptom of Calcium and Phosphorus deficiency.

Now if coco should be more like hydro then a ph level of 6.0-6.3 is too high and at that level Potassium, Calcium, Iron, Boron and Manganese is completely locked out and when it reaches 6.3 Phosphorus becomes locked out. Maybe I can make out some yellow and translucent spots and maybe some leaf browning at the margins (Potassium deficiency) and since I already said some leaf tip burning (calcium deficiency) I don't really see the signs for Maganese which is yellow/mottled young leaves nor do I really see the signs of Iron deficiency which is the tissue between veins on young leaves becomes pale or white and I'm not really seeing the signs of Boron deficiency which is grow points die back and young leaves become yellow, distorted and form unnatural rosettes.

So based on just what I'm seeing and the ph values you gave it sounds like coco ph should be treated like soil and your ph is too low locking out Phosphorus Calcium and Magnesium. My advise therefore would be get the ph up to 6.5 but avoid adding any additional nutrient for the fist watering that you use to raise the ph because since several nutrients have been locked out they're likely sitting in the soil unused and adding more could create a toxicity issue. Then again I hear coco doesn't really hold nutrients the way soil can so the toxicity concern might not be there. The next feeding after the ph is higher then it would be okay to add more fertilizer but really the buds are looking like they're getting sort of close and so it might be time to start cutting back on fertilizer? Oh wait I see you said week 5 so you got a couple of weeks before worrying about stopping fertilizers.

Finally though, I can't ignore my lack of experience with coco, all I've said is based on what I see in your photo, distance from the light, temp, humidity are all fine so it's none of those things and so all that really leaves me to go by is ph. I'll attach some charts that I used to determine what should be happening with that ph for both soil and hydro and I'll add a sick plant chart to I used to determine what should be going on if the nutrients in question were locked out or deficient. However since I have no experience with coco my suggestions should be taken with a grain of salt and you should pay more attention to someone experienced with growing in coco.

 

[cancareent]

HempKat Creeperpark Thanks for the detailed reply guys, I will try out your suggestions. I was told to treat coco like hydro and to keep it between 6.0-6.3. Is that not the correct range for hydro? I have been putting 4 ml/gal of botanicare cal/mag ill try to bump it up to 6 and see if that helps. Thanks for the detailed reply guys- you are what make me love to continue growing and learning!

 

[HempKat]

HempKat Creeperpark Thanks for the detailed reply guys, I will try out your suggestions. I was told to treat coco like hydro and to keep it between 6.0-6.3. Is that not the correct range for hydro? I have been putting 4 ml/gal of botanicare cal/mag ill try to bump it up to 6 and see if that helps. Thanks for the detailed reply guys- you are what make me love to continue growing and learning!

Well if you look at the second of the three charts I posted the correct range for Hydro is 5.5 to 6.1 and with 5.8 being the ideal value. Again though the signs I saw in your pictures suggests that it should be treated more like soil but since I have zero experience with coco I could be wrong. One thing I do know about coco though is it doesn't hold any fertilizer in the way soil does which means you have to have fertalizer in the feeding you give it every time where as in soil you can usually skip a feeding every now and then and just give water which then gets the plant to use the nutrients being held in the soil.