yellow leaves...nute lockout?

[highgrade]

ive got 4 k2 and 8 ak48 plants from nirvana in veg under a 600w grolux fed on cf 12 of vitalink grow and vitalink silicon, they're 4 coming on 5 weeks old and im getting lower growth turning yellow then to brown and dying off. some of the upper leaves are curling inwards and the very tips look to be going brown I cant get any pics till lights out in 5 hours can anyone help?.

 

the plants are in 13cm square pots of clay pebbles and fed passively ph is 5.7 and cf 12,

 

would I be bet flushing with plain ph adjusted water then running on formulex for a while?

 

 

any help appreciated...ill add pics after lights out.

 

 

EDIT: also jus taken another look and got internodal growth setting in on one of em...

 

 

 

Edited April 26, 2006 by highgrade

[SukonmiSkunk]

seems to me they are starving, I measure in ppm so I would say up the nutes to about 1600ppm, I am not sure what that is in cf... but the bottom leaves turning yellow is a nitrogen diff, are there dark and light green patches on other leaves closer to the crown also?

[highgrade]

seems to me they are starving, I measure in ppm so I would say up the nutes to about 1600ppm, I am not sure what that is in cf... but the bottom leaves turning yellow is a nitrogen diff, are there dark and light green patches on other leaves closer to the crown also?

 

 

cf of 12 is 840 ppm on my meter,

 

crown as in top of plant?...on some of the leaves they're starting to look a little patchy not solid colour at all and on the odd plants theres little black patches too,

 

so i shouuld mix up a grow solution of close to 1600ppm? this wont burn them will it?

 

sorry bout all the questions this is my first grow..

Edited April 26, 2006 by highgrade

[Tom]

theres little black patches too,

Doesn't sound like a lack of nutrients to me, check out this link and see if anything matches, also check under the leaves and on the stalks of the plants for bugs, you may need a magnifying glass as some bugs can be pretty small.

 

Bump your PH up to around 6.0 too.

 

[highgrade]

looks like a potassium deficiency from that link above ill up the nutes a little in the morn,

 

and post pics..

[nitram]

I am going to wait for your pics before I jump in and hypothesize wgat up.

 

 

So in you first post you said :

 

the plants are in 13cm square pots of clay pebbles and fed passively ph is 5.7 and cf 12.

 

decent size pots !

 

 

would I be bet flushing with plain ph adjusted water then running on formulex for a while?

 

YES. you woulod be better flushing with PH'ed water.

As Tom advises.

 

 

any help appreciated...ill add pics after lights out

 

No worries highgrade, Hay ! What medium appart from hydrotron pebbles (if any) ddo/are you using ?

 

goodluck highgrade

[SukonmiSkunk]

if your ppm is at 800.. it is most definately starving.... just up the ppm to 1600 and that will fix everything... I run my ppm at 1800... so see how that goes, you might be able to up it some more....

 

what water are you using?..

[thc24]

Hi mate i had the start of black mouldy spots on under leaves last week, by reducing the amont of water through pots and compensating with higher ec it disapeared over night.

 

Might be worth inspecting the roots for bug damage but more likley over watering.

 

your nute level 800 i dont Know what that works out tobe in ec but if SS says there hungry id think that was enough to get me running to the shop,

[Chev]

I second the motion of upping your PPM for sure, your girls need it!

[F420]

I would up it to 1400 and see how they go with that.

I would also stop giving them silica for a few weeks intil the plants look good again.