yellowing plants in fact yellow as can be

I have 2 Durban poison and 1 skunk #1, 1st db going yellow with few browning leaf edges, 2nd db yellow as fook with browning leaf edges and the 1 that looks the healthiest sk#1 is now going yellow around the bottom leaves. all on grow for around 3 weeks

they are growing in cocoa under a 600watt light around 5ft away. i have been feeding them biobizz grow with root juice mixed. i feed once every 2 days and was at about 2 thirds strength.

temp around 78 degrees, PH 7 and humidity 50%. thought that i may have given them a nutrient burn so flushed and re-potted 1 week ago. still no joy seem to not be growing at all but not getting and worse (thankfully).

has any one got and advise on what to do. i have left pics.

the greenun.:jointsmile:

are u still giveing it the amount of nutes that u were or did u cut back or stop all together

Coco fibre?
What's your runoff pH? Those plants are starving; if you are feeding them and they still look like that, it's a lockout.
Coco is basically a hydroponic medium and your pH needs to be lower than for soil, down around 5.8 ish.

cheers for the response bro.

i have cut it out all together for the last week, thought that i was burning them.

what do you suggest?!?!?!?

get them back on nutes right away!!! 5.8 ph is perfect as stated earlier. coco/perlite mixes are straight hydro and have no inherant nutes. be sure to feed them with every watering. depending on the exactitudes of your medium you may have to water more than once per day to keep the moisture level just right.

also you say that your 600 watt light is 5 ft away? as in 60 inches? if we are talkiing about an HPMH or HPS that has to be so much closer!!! With your plant taking in these nutes it will need the light to process them otherwise your plant will suffer.

I have 4 600 watt HPS bulbs and my canopy sits about 8 to 10 inches away.

hope this all helps.

Thanks for the advice :thumbsup:

I will do exacetly what you are suggesting and keep ya posted. Is there any thing else you suggest?. Do you think that I should place a fan facing the light so they don't get too hot?.

whats the temp by the light its 5 feet away but maybe, do u not have a fan already? i couldnt tell from the pics

I have placed a fan blowing straight onto the fan and have placed it about 24 inch away from the plants. I've re-potted the skunk#1 as the pot it was in was quite small. not only are the leaves going very yellow now but the stems are as red as can be and some of the upper leaves are getting a red like dot effect on them. its all becoming so stressful so many thanks for ya help bro.