magnesium def? pix

Hey All,
They don't look too great:(
Leaf tips are burnt and turning upward.
Some brown spots.
Kinda droopy even though i'm not overwatering-- I water every 3 days about 3 cups of h20 tap, shelved for 24 hours to dechlorine and phed to 6.5 to 7.
Some yellow and green stripes on the leaves.I feed every other watering ffgb 2.5 tsp per gal.
run off ph is about 7 i'd say, I'm using the dropper/vial testers.
400w air cooled hood
rh is about 35%-48%
There about 2 mo old, so far have 1 showing as a girl! So i'd like to get this cleared up so I can take some healthy clones!
THanks for any diagnosis you can come up with!
Ughh! I'm almost halfway there!
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heres some more pictures

I don't know a thing about soil but have you seen this link? It's got some great info.....hope it helps.

International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles!

Hey Weedhound,
As a mattera fact i did:) I can't make a definate diagnosis. It could be mg, or N, but I've been feeding them almost full doses? I'm wondering if maybe my ph is to high. I'm using fill the vial and add drops and compare color method, and runoff is green in color after the drops are added and green = ph 7, but maybe its 7.1 or 7.2 or maybe 6.8.
What nutrients would get locked out with a ph of 7 or a tisch above 7?

need more info....soil mix? Temps? Watering schedule?

If I had to guess I would say you let them get very dry by mistake then over compensated by watering too often. You might have other issues as well or it could be a root problem. More info please.

- Slow -

sorry, just re-read your first post. 3 cups? How big is the pot? You need to learn to water by weighing the pot (By hand....get a feel for a dry pot and a real wet pot). Also, drainage?

- Slow -

hello mate,Magnesium gets locked out of soil growing at ph levels of 2.0-6.4
Magnesium is absorbed best in soil at a ph level of 6.5-9.1 . (Wouldnâ??t recommend having a ph of over 7.0 in soil) anything out of the ranges listed will contribute to a Magnesium deficiency.

Thanks all for your feedback!
Pot size= I'm guessing there 1 gal pots, also have perlite mixed into soil.
So if my ph is just above 7, should the ph of my water be like 6 to to bring the soil ph down to a better level?

say its time to transplant to a bigger pot and perhaps it may help to fix some of the problems your having right now, also you might use epsom salt or cal mag to give your plants a source of magnesuim to see if it helps the problem dont really notice any upward leave curl in the pics but darker veins and leaves curling upwards are usually a good indicator of a magnesuim deficiency.

I was thinking they may be rootbound too, looking at the drainholes, I see roots. So-
Heres my dilema...
I don't have room for 9 plants in 3 gal. containers in my cabinet. Max I can fit 4 3 gal containers. Bye this time I was hoping I'd see more pre-flowers and be able to pull the males. Sadly not the case. I've got 1 showing a girl! So, can I go 12/12 with them rootbound a few weeks and see what I got, then transplant the females?
thanks all
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