Top flowering leaf tips curling >:(

[DrGreenThumb]

We got 2 plants on a hyrdo set up (see our journal for more info) and they are into week 5 of flowering.

The top leaves of the cola are slightly burned on the tips OH NOES!

there is only 75% bloom nutes in the resevoir and we got the NFT running water across the roots 1 hour on, 1 hour off and then a 6 hour break at night to gather oxygen or whatever. We mist the plants on a regular basis (we use about 1 litre a day of ph balaned water from the tap).

Could it be nute definciency? or maybe a Ph problem? remember they are flowering. we keep the water at about 5.5ph, slightly acidic, as this was the advice taken from other hydro growers. should i change the ph to maybe 6.5? i maybe i need to flush the roots with pure water.... that would be a problem as we would have to take the res off and throw water over the root matt and these girls are about 5' tall monsters; really hard to move threm through danger of bending them.

anyway, we neeeeed your help MJP

 

[Elephant Man]

Sorry, aren't they at like week 4? or 5? Sounds like you need to cut back on ferts just a tad, maybe to 50%, don't do anything drastic, your girls are adapted now and straight water or messing with the roots could shock them. This kind of thing is done in soil, but soil is more forgiving than hydro...so I'm told.

Tenths of a point of ph are a big jump, going a whole point at once would definately cause shock, taking ph from 5.5 to 5.8 is a more reasonable movement...but to make N (burnt tips) less available, I'm pretty sure you would want to be going the other direction with ph. I'm not a hydro guy but I remember some do run slightly different ph in flower/veg....I know Kade does...perhaps there is abit of info in one of his threads.

 

[KADE]

yes i do. 5.4-5.6ph when flowers are showing... plants use more of different nutes in flowering then vegging... this allows them to be a lil more available.... plus... my grow schedule tells me too.

 

[DrGreenThumb]

cool thanks for your help guys