This is my first grow but it has been a long time coming and I've done alot of research. With that said I have come across my first problem.

My seedlings have started to dry out and brown at the very tip of their newer leaves. some of them are also curling a bit at the margins of the leaf. The weird thing is the bottom pair of first true leaves are fine, but all the others arent...

My PH stays between 5.5 and 6.2 while my ppm stays between 250 and 450. On one occasion pH was as low as 5.3 and ppm was as high as 720.

Also until a couple days ago our humidity was staying around 28% during light hrs and 45% at night. Temps have always stayed between 68 and 78.

Any help with this problem would be very much appreciated.. the link below is my other thread that shows pictures of them.








Help..1st indoor hydro grow..feminized Arjans Ultra Haze/Jack Flash

First of all your plants are looking a little stretched for 1000w.
How far is the light from the plants? You may need to lower it.
They really don't look to bad considering the varying PH and PPM they've been receiving.
A little bit of burning could be from your low PH or the 700 PPM you hit them with.
i think once you get a little more consistent with these things they'll colour up nicely and settle down.
Try and keep the PH more consistent 5.8 - 6.0 and they should be able to handle no more than around 250-300PPM at this age.
What's the PPM of your water before you add nuts?
Those strains you have are excellent so I understand you don't want to mess them up. I don't think you have to much to worry about at the moment. Your just seeing the result of a little over fert' and PH fluctuations.
All strains are slightly different in what they like and you won't know until you've been growing that strain for a little while. Your in the 'finding out' stage so just keep a close eye on what your doing, which you are, and you'll learn what they like and what they don't.
P.S. Looking forward to seeing some Jack Flash, that gear sounds real good.

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I don't see a problem with growing small quantities of cannabis to supply ones own medicinal needs. I do not par-take in, or condone, the illegal growing of cannabis for commercial purposes.

Man you are right on with that analysis. Yea I have gotten the pH and ppm alot more consistant. The PPm has gone back up to 430
I guess because Im having to readjust the pH every day to keep it between 5.5 and 6 so today I am flushing the whole system with floraclean and I will be refilling it with a solution that just has grandma engy's H-2(humic acid) and a little bit of vitaboost, the ppm will be 30-50. With this solution runing for a week they should recover, the new growth already looks better. 10/10 Jack Flash germinated and 5 have already come out of the rockwool.

Yea the light was to high because I thought maybe the heat/light intensity was maybe the culprit that was drying out their leaves. It is obvious now that it was a mix between leting the nutes go way to high and the very low humidity. We now have a centrifugal fan blowing through the light, but with the light now 2 ft away from the plants the temp will rise to a high of 83 sometimes even with the new fan. we even have a window right next to the closet that is kept open bringing fresh cool air in. We also have an ocilating fan blowing the hot air under the lamp around. Any ideas that would help keep the temp back at 68-78 would be nice.

Oh and thanks alot for the reassurance Mammath...being a hydro noob I do alot of research and come up with pretty good ideas of how i might be doing something wrong but I am never completely confident in my diagnosing...ppl like you are a pretty good remedy for that.

if they are around 4-5 inches tall with 4 nodes including the new growth...how far away from the light should they be(1000w)

Keep an eye on that PPM. Over 400 maybe a little high but see if they can take it. The good thing with hydro is you get to see instant results, good and bad.
Are you recirculating? I've never been a real fan of that type of hydro. It's a lot harder to keep things consistent. I always run my hydro to waste. Then you just have to keep your resi right and check your run off now and again for salts build up.
Having your 1000w 2ft maybe a little close. Do the back of the hand at plant level to feel if it's too hot. I'd say 2 1/2 to 3ft at the moment.
What sort of shade do you have? Can you pull some heat straight off the lamp via an inline fan and some ducting from the shade? 83F isn't too bad but maybe a fresh air duct into the area would help if possible instead of that window.
Keep me posted.

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I don't see a problem with growing small quantities of cannabis to supply ones own medicinal needs. I do not par-take in, or condone, the illegal growing of cannabis for commercial purposes.

The light is more like 2.5 feet away i measured it today. We flushed the system twice with Ph adjusted water and some Flora Kleen. We are going to drain the remaining Ph water tomorrow and add the normal nutrient solution. We let the adjusted water run and drip most of the day startin out at 5.5 Ph. I was not watching for a few hours and somehow it jumped up to 7 PH so I shut off the system and we will drain it and add the adjusted nutrient solution like i mentioned already. Average temperature is around 79F and RH is around 40-60% average. A freaking dog attacked one plant, do not ask how but it happened. It is recovering well and more pictures will be posted asap. They are looking pretty good.

alright plants new growth is looking good...keeping the ph at 5.5 - 6 right now but me and my roomate are having to change the readjust it twice a day atleast...Im just wondering if this is normal and if the daily fluctuations from 5.5 to 6 are bad?..Ive heard that chasing the ph isnt good. I even drained the system and flush it with a solution that is supposed to clear up the salt build up. Also the Ph seems to go up a point or 2 after every watering...which is 5 times a day for 30 mins. Any ideas on how to stablize this a little bit better? On monday the upgrade kit to make the waterfarm system recirculate is coming in and i know that should help some...

ill be posting picture soon gotta borrow a friends digital

Good to here some aspects of your grow are improving.
Unfortunately I am not a waterfarm savvy user but there are plenty on RIU.
Maybe do a tag search for 'waterfarm' and PM someone who's running one that can help you with why your PH is fluctuating so much. It's sound weird for it to jump so much.
Here's a link to one thread I found. This guy seems to know what he's doing.
Waterfarm Mods & Tips
All the best.

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I don't see a problem with growing small quantities of cannabis to supply ones own medicinal needs. I do not par-take in, or condone, the illegal growing of cannabis for commercial purposes.

Thanks alot...yea i did some reading on Ph and PPM chasing and I read alot of ppl are having trouble with the hydroton clay pellets making the Ph rise consistantly. I think I might try using ph'd tap water instead of distilled water on my next resavoir change. Thanks for the link ill check that out

Hydroton Clay. It's hard finding a nice neutral medium that doesn't leach shit into a system these days isn't it? I'm a coco coir man myself with a totally different set up so what do I really know.

Get access to some rain water if you can. That's the shit I believe. God given.
Try to make your environment as natural as possible, yet extremely counterfeit and better than nature, that's the quest!

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I don't see a problem with growing small quantities of cannabis to supply ones own medicinal needs. I do not par-take in, or condone, the illegal growing of cannabis for commercial purposes.