Drooping Cannibis leaves

[Shultzs999]

Hi everyone I tried to post this issue the other day but got called out to work so I’ll try again. I have 6 x Shishkaberry plants that went into flower 7 days ago and they all looked fine but now 1 tank with 2 plants is looking sick,thin clawing leaves and the whole plant looks droopy apart from the tops which have preying leaves. I don’t think it’s environmental as I have all the parameters dialed in air temp 27c, leaf temp 25.5c , humidity 60% and vpd at 1.09 kpa water temps a bit high at 22.5c. Plants are growing in Nft hydroponics tanks, led lights x 2 at 500w at 100mm above recommended height,inlet fan running 20% less than outlet fan given negative air presure and 2 x oscillating wall fans pointed at the tops of plants. EC at 1.8 and PH at 5.9 and staying steady in all tanks. I’m baffled why 4 plants are doing well and these 2 looking so bad. If anyone has any idea what’s going on I would be grateful for your input my thoughts are somethings to do with the roots but I can’t see any obvious signs. This is only my 2nd year at growing so still leaning . First picture of roots is the droopy plant second picture of roots is good plant.

 

[Bluey]

Have you checked your leaves with a loupe for pests?

 

[Wayzee]

I been waiting for someone else to have a suggestion but I'll go first,
What are you feeding them? Do they all get the same amount?
It looks like pics I've seen of "the claw" from nitrogen toxicity but I could be wrong,. Have you tried flushing her with water? Most people on here growing in water use a "hydro guard" for keeping the roots free from root rot and other root issues, might be worth looking into if you not already onto it.
Oohp bluey beat me to it haha.
Something else I noticed is 60rh and 27° at flower time might be a bit high. ?

 

[Shultzs999]

Yes I’ve checked for bugs and all clear I did have thrip when they were in veg but I caught them early and got rid of then quite easy. Thanks for reply

 

[Shultzs999]

Hi Wayzee good to get some feed back I feed Dutch pro at all equal quantities as for nitrogen toxicity I thought this myself but for that I would expect to see dark green leaves so ruled this out. I use 1mm per litre of silver bullet in 40 ltr of water the first week and providing every thing looks ok I feed 1/2 mm per ltr every 2 weeks after that and as for humidity at 60% I do this when the weather really hot I helps keep the vpd in check as normal temps in the room run at 26c for first 3 weeks then drop down to 24c for the last 5 weeks. Thanks anyway