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kronik1 · #8 (**permalink**) 05-01-2008, 01:52 AM

Hi all, first a big thanks for the replies - they are greatly appreciated!!

Let me provide some more background info which may help diagnose the problem...I apologize for the length - I just don't want to miss anything that might help provide a clue.

Ok, I started with 5 sprouts and only 1 survived - I used a humidity dome during germination and when they sprouted, I turned on a T5 light which was right over the humidity dome (since I read that T5s need to be only a few inches from the tops). Big mistake - I woke up the next morning and all my sprouts were fried (temps hit 92f). They were all wilted and the stems were dark purple (I assumed this meant heat stress).

I thought they were all dead so I turned off the light and thought I'd just try again with a new batch of seeds. After about 3 days, I looked in my closet and lo and behold one sprout had come back to life (now standing upright and the purple was disappearing from the stem). I had used grodan starter plugs and the taproot was sticking out the bottom so I quickly soaked a 4x4x4 rockwool cube in 5.5 ph water overnight and then inserted the starter cube. I also abandoned the T5 for my 400w CMH (which I started at 18" from the top which I read was a good distance).

I was worried the couple of days without light might have done some damage but the plant took off like mad! It was practically growing by the hour!

I waited 3 days before watering. I have an ebb and flow system but I don't want to put the single cube in it yet as I am waiting on some more seeds. I figured I would manually water this one until my soon to be other plants got going.

I wait until the cube starts to dry out a little (around 3 days) then I dunk the cube in a resevoir for around 10 seconds or so which seems to thoroughly drench the cube. I figured this is the same way the ebb and flow system would water it (as the bottom of the cube would sit in the flooded tray).

Ok, so that's the story... now to address some of the very good theories that have been presented....

PH Problems - I don't think so - for the first week I used PH 5.5 water, then the second week I used the weaker Lucas formual 0-5-10 which brought the PH down to about 5.9 by itself, and now I am using the full 0-8-10 formula which brings the PH down right to 5.5 by itself!! I am using a good, calibrated HANNA PH meter.

Root Bound - I chose the 4x4x4 cube because my ebb and flow system can fit 8 5.5" cubes (too tight for the hugo blocks so I went with the next biggest). The plant can't be root bound yet as the roots have not even penetrated the cube.

Over/Under fertilizing - I chose the Lucas formula because it is supposed to be simple. He is very adamant about NOT adding anything else to the mix. Tons of growers report success with his formula so I don't see how that could be the problem unless something is getting locked out. My TDS is at 1100ppm, .5 conversion scale.

Over/Under watering - I admit, I am pretty lost here.... I wait til the cube starts to dry out a little before watering, but then I think to myself - all the instructions I have read regarding ebb and flow watering schedules say to water for around 15 min every 2-4 hours... that seems like a hell of a lot!! That would mean the cube would always be soaked!

Again, all feedback is greatly appreciated!!

#8 (permalink) 05-01-2008, 01:52 AM
kronik1 Registered User Join Date: Apr 2008 Posts: 2	Hi all, first a big thanks for the replies - they are greatly appreciated!! Let me provide some more background info which may help diagnose the problem...I apologize for the length - I just don't want to miss anything that might help provide a clue. Ok, I started with 5 sprouts and only 1 survived - I used a humidity dome during germination and when they sprouted, I turned on a T5 light which was right over the humidity dome (since I read that T5s need to be only a few inches from the tops). Big mistake - I woke up the next morning and all my sprouts were fried (temps hit 92f). They were all wilted and the stems were dark purple (I assumed this meant heat stress). I thought they were all dead so I turned off the light and thought I'd just try again with a new batch of seeds. After about 3 days, I looked in my closet and lo and behold one sprout had come back to life (now standing upright and the purple was disappearing from the stem). I had used grodan starter plugs and the taproot was sticking out the bottom so I quickly soaked a 4x4x4 rockwool cube in 5.5 ph water overnight and then inserted the starter cube. I also abandoned the T5 for my 400w CMH (which I started at 18" from the top which I read was a good distance). I was worried the couple of days without light might have done some damage but the plant took off like mad! It was practically growing by the hour! I waited 3 days before watering. I have an ebb and flow system but I don't want to put the single cube in it yet as I am waiting on some more seeds. I figured I would manually water this one until my soon to be other plants got going. I wait until the cube starts to dry out a little (around 3 days) then I dunk the cube in a resevoir for around 10 seconds or so which seems to thoroughly drench the cube. I figured this is the same way the ebb and flow system would water it (as the bottom of the cube would sit in the flooded tray). Ok, so that's the story... now to address some of the very good theories that have been presented.... PH Problems - I don't think so - for the first week I used PH 5.5 water, then the second week I used the weaker Lucas formual 0-5-10 which brought the PH down to about 5.9 by itself, and now I am using the full 0-8-10 formula which brings the PH down right to 5.5 by itself!! I am using a good, calibrated HANNA PH meter. Root Bound - I chose the 4x4x4 cube because my ebb and flow system can fit 8 5.5" cubes (too tight for the hugo blocks so I went with the next biggest). The plant can't be root bound yet as the roots have not even penetrated the cube. Over/Under fertilizing - I chose the Lucas formula because it is supposed to be simple. He is very adamant about NOT adding anything else to the mix. Tons of growers report success with his formula so I don't see how that could be the problem unless something is getting locked out. My TDS is at 1100ppm, .5 conversion scale. Over/Under watering - I admit, I am pretty lost here.... I wait til the cube starts to dry out a little before watering, but then I think to myself - all the instructions I have read regarding ebb and flow watering schedules say to water for around 15 min every 2-4 hours... that seems like a hell of a lot!! That would mean the cube would always be soaked! Again, all feedback is greatly appreciated!!