I think that this is a Toxity, perhaps through pH, any help please

Hi all!!

I'm growing Blue Mystic in soil (BioBizz light mix, plus extra perliite), and an inch or so of clay pebbles at the bottom of the pots, and feeding With Bio-Grow, Bloom, and Top-Max. I've only reached 1.25ml per litre of Bloom, and 1ml per litre of Topmax, which doesn't seem that high for 5 weeks from flip, about 3 and half weeks flower I guess. Water is from tap, left to stand for 2 or 3 days, pH around 6.3-6.5.

I've been doing some reading and am thinking about raising the pH to more like 6.5-6.8... any thoughts??

Anyway, you can see from the pics below my unhealthy plants... would really love some advice to sort them out....Please!

Hi there, other than the few effected leaves the plants look good. The yellowing of the leaves in flowering would originally suggest N deficiency, but the orangey tips kind of suggest a zinc deficiency but im not 100%.See this image here: and see which it looks like most.
View attachment 2213713

You've got some purple stems there aswell which could be genetics or it could be a Mg or P deficiency, in which case I'd make the PH a little higher than normal, to around 6.6-6.8 to assist in uptake of those two elements, heres a handy chart.
View attachment 2213714

Thanks, it looks either like its Zync, Nitrogen, or both. Of all the nute guides i've seen, that's a new one so thanks!! The water pH one was a bit much though, I'll try and digest it fully later over a J

Thanks for the help MorroN

Yeah get that ph up over 6.5. This is a typical N deficiency. Yellowing starts at the bottom and works its way up, if left alone the leaves will yellow brown then fall off as the plant uses the N up from the leaf. Buds look good for week 5.

jpockets420 said:

Yeah get that ph up over 6.5. This is a typical N deficiency. Yellowing starts at the bottom and works its way up, if left alone the leaves will yellow brown then fall off as the plant uses the N up from the leaf. Buds look good for week 5.

Click to expand...

I watered them today at 6.7, and have started putting a little more Biogrow in the feed too to sort out the N def.

Thanks for the compliments, I've been growing for a year, and have ironed out a lot of problems... and keeping the canopy 1" away from the CFL's gives me some mental frosty budds, even if the quantities are pretty low. My plants are only reaching 16" fully matured, they are a particularly small indica.

Hettyman said:

I watered them today at 6.7, and have started putting a little more Biogrow in the feed too to sort out the N def.

Thanks for the compliments, I've been growing for a year, and have ironed out a lot of problems... and keeping the canopy 1" away from the CFL's gives me some mental frosty budds, even if the quantities are pretty low. My plants are only reaching 16" fully matured, they are a particularly small indica.

Click to expand...

Just another thing to add, N deficiency and yellowing of leaves some leaves is fine in late flower. The plant will take up the nutrients/food in the leaves and use them to help power bud growth. Just sayin' so you dont go too crazy and burn the plants or anything.

Good growing

Thanks man, its ok I switch to pure bloom feed towards the end, and then just water for 2 weeks to use up the remaining nutes in the soil, but without flushing the soil through