Plant sprouted 01/22/11 on a water, feed, water schedule starting with 1/4 strength around 3 weeks old, next feed was with half strength, last fed with full dose of nutes and calmag and transplanted from 1g to 3g pot. Soil is promix hp. Last run off was 6.0, every one previously was 6.5. water is from tap, sat out for 24 hours and ph'd to 6.0. Under 200w cfl. temps are 73 day, around 58 night. Strain is ak48. Have a Afghan haze that has received the same treatment no symptoms at all.
I'm having similar problems; from what I've read it may be related to Mg/Ca deficiency, both of which can be provided with dolomite lime. My soil tends towards the acidic side as well, so hopefully it'll take care of all my issues (just added some in tonight). Fingers crossed!
Lack of Mg? I've read some species require more than others; also, the nutrients you're using may not have a ton of Mg to begin with.
I can't say I've ever seen a specific amount (PPM) of Mg needed (and for most of the micronutrients, for that matter). Personally, the rule of thumb I use is "enough to avoid showing signs of deficiency." Reading through your OP though, I'm really not sure. Most plants should be able to get by the first few weeks with little to no added nutes at all....so other than nute burn (or pH), I can't come up with a rock-solid answer why your pictures look like Mg deficiency so early on.
It is very frustrating not knowing what this is or how to help. I wish it was nute burn but it doesn't develop like that at all, at 5 weeks from seed could it be lack of food?
doubt it unless your soil is crap, make a foliar spray w/epson salts.. It helped me get through my recent spout, mine was worse but within a week they seem back on their feet after giving it a foliar spray twice a few days apart with a foliar flush to get the deposits off inbetween.. your roots are having issues, are you over watering it?
Water about every 5 days, stick finger about 2 inch and feel, also do the 'lift' test, water if dry. Should I still foliar feed with Epsom salts after I hit her with calmag? If so how much should be mixed up?
Thinking now it may be because if the tap water. Ppm is around 250, but this is with those paper strips so it's not exact. According to that link, above 200 can lock out mg. Still... Why is the afghan haze 3 perfect?
Different plants have different needs and strengths so one might be a little bit more vigor then the other, it just depends on the strain. Before you get your seeds you should read up on it and if they are immune or easily get sick.
Gave plant a spray with Epsom salts/water. Does not seem to have helped. Really wish this could get resolved! Not sure what else to do at this point. New growth looks fine but all the fan leaves are showing these spots that slowly take leaf over until crispy.
A) What do you mean by "not...helped?" I wouldn't expect the brown spots to go away....those areas are brown because of cellular death; they're not just going to regenerate. The real question is whether the problem is continuing to get worse..... B) It's only been a few days! Give it time!
Not helped as in got worse is what I mean. Yes it has been one day since foliar feeding, but 4 since it got cal/mag. I apologize if I did not mention it. Is this definatley a deficiency or a lock-out? Not sure what should and should not be done now and can another foliar feed by ok?
I would say that it is a deficiency, if you are confident tha tyour PH is stable. I think you should be adding the cal-mag with every water feeding. Generously at first to correct the problem, then a moderate amount for maintenance. The leaves witht he spots will most likely get worse and die, but the importance is in the new growth. If less than half the plant is affected, I just cut the bad leaves off so I don't have to constantly stare at it. I am not a huge fan of foliar feeding so I am a little biased. I believe getting the cal/mag into the plant through the roots would be much more quicker/efficient than through the leaves. But I'm sure a number of people could disagree with me. Are you calculating your PH with strips as well? If so, I would invest in a cheap digital PH meter and make sure your PH is correct. I hope everything goes well.
Ph was stable at 6.5 until last water/feed. Runoff was 6.0 but these signs showed before when runoff was 6.5. Using a drip test for ph and have a digital on its way in the mail. Thanks for the help Marduk!