Why are my plants growing so ssslllooooowww

[Sir PsychoHashy]

You need to pot up for sure, and while you're doing it have a good look at your roots.  You want a nice white to light tan colour, and a fishbone effect, with a nice clean smell and no gelatinous coating.  I'd be surprised if they're not rootbound in those little pots after this long.

 

Not completely sure what your deficiency is, but it could be magnesium, newer growth looks fine though.  I personally have no problem with using calmag additive as a precaution, especially with coco (even more especially with cheap Bunnings coco), but as Frank said you shouldn't need to with coco specific nutes.  Often with many deficiencies the cause is related to PH or rootzone issues, and simply adding extra shit without addressing the cause will not help.

 

Overall they don't look too bad, pot em up and give em a couple of weeks recovery and flip your lights and you'll end up with some big bushy beasts by the end of stretch

[cap'n yNg]

+1 all the above, including being bad at trouble shooting .

defo need potting up man! give the roots some space to grow and the plant will follow.

apart from that dodgy leaf they look pretty healthy.

Edited September 10, 2014 by capt yNg beard

[sols]

over fertilising can cause nutrient lock and plant wont take nutes or can kill it. you don't need to use every nutrient you listed, use 1 only, seasol is great. when in flower give nutes low in nitrogen. if leaves are healthy dark green then no extra nutes required. most brands of nutrients have same or very similar formula anyway.

[The Green Goblin]

What light are you using? How close? What brand and what kind of bulb?

 

Also get bigger pots.