Seedlings dying one after another. HELP!

Hello folks. I've been scouring this sight for some help with a problem I can't seem to narrow down and would love some insight from y'all. In the past several weeks I have killed more than 10 seedlings(some bought, some bagseed) and am getting frustrated.they all seemed to have the same problem but I cannot find a specific answer. They all germinate well(100% actually) but after 4-7 days their dead. I germ them in a dome on a heat mat. Once they sprout and open up a little put them in my cabinet for heat and 5-6" from 42w cfl without the dome. I've used coco/perlite mix and straight coco for mediums with same results. Some were moistened with softened tap water, some with pure distilled and two were with distilled with cal/mag and all same results. My humidity is 35-40 and temp is whatever I want but have been keeping it at 74-77. I have two computer fans, one in one out and a 4" fan blowing on the seedlings 24/7. I'm using 1,2 sometimes three 42w 6500k Cfls(24/7) keeping seedlings 5-6 inches away all with same crapy results.PH is always in the 5.7-6 range and no nutes used. The results are the plant does well for first 1-2 days after germinateing but then starts to deteriorate. As soon as the true leaves come out they start to brown and crisp and point straight up but the cotyledon stay green and healthy on all if them. Then after 3 days of zero growth they are toast. Roots usually only 1-2" long but appear white and healthy but plant is dry and withered. Any info or suggestions would be greatly appreciated and thanks for your time.

got any pics, at first I thought you were describing "damping-off", which is cause by pathogens in your grow medium...but I'm not to sure bout that since you said the root is fine, and damping-off usually hits the root and stem areas first and the plant kinda just falls over and withers away real slowly...google the term and see if it fits what you've been experiencing!!

It sounds like an overwatering issue, let the medium dry much more between waterings. Seedlings don't like medium being constantly wet.

Thanks folks for the replies. I do have some pics but being my first post am i allowed pics.And would need some time to figure the process out. They stay standing and never fall over and roots always whites so damping off was put on back burner. I do flush the coco out with 1/2 gal of phd water(4" pot) and let it dry for 1-2 days before placing seed in. Have used coco/perlite and straight coco with same reults. I have also tried a couple dry plantings with 1-2mil's of h20 to moisten and same thing happened. I was hoping being a newb that I was over watering them but with the dry starts and failure I think otherwise.UPDATE:the only one I haven't cremated yet has actually started to repair the brown crisping true leafes and begun sprouting another node with very tiny true leaves all within a 24 hr period. It looked like and was written off in my journal as deceased(first true leaves shriveled brown and crispy with no growth in 3 days). I'm amazed. Only thing different was I watered 2 days ago at day 6 with distilled AND cal/mag @ 5ml per gal as I discovered its needed with distilled h20.BUT keep in mind I've used tap,bottled,snow melt and now distilled with same outcome. Not sure what it means but maybe will pinpoint something. Thanks again folks.

Checked on baby this morning and its back to shriveled and sick looking. Stem very skinny but still standing and leaves have dry browning look and growth has stopped. This one is 13 days from sprout today and is only 1.5" tall and now knocking at deaths door.

I second damping off. I've seen plants dead from damping off with a nice healthy root system below the point where the stem was turned to mush.
Lookup those pictures, I'm sure you will recognize it.
Get new medium, don't water so much, keep the air moving. Good luck.

PH should be 6.5 on the dot always. You may be watering them too much. let them dry out a bit before you water them again. I don't know what brand of Cal-Mag you use but I use Botanicare Cal-Mag and it is used at 2 teaspoons per gallon.

Thank you all for the replies. I will begin research on damping off and learn how to avoid and be more cognisent about the waterings and see how it goes. Thanks again.

Usually with damping off the stem will discolor and shrink in size at and above ground level. Here's kind of a classic pic of seedlings (not weed) that suffered from it. A greenhouse producers nightmare, it happens quick and is pretty much 100% fatal. Lost 12,000 tomato plants overnight once.

sowing the seeds too deeply will also cause problems. i never sow deeper than 1/8". GL

Keep your plants in the hum dome (or use sandwich bags). Don't blow air ON them, but around them. Get more light, a cfl an inch away from every plant. Heat mats aren't necessary and often cause issues. Overall Diagnosis: your seedlings are drying up.

I agree with mrcrc420, I don't think seedlings like a fan blowing on them. I always leave the dome on crooked for a couple days to gradually get them used to some air before taking it off altogether. I don't know much about coco because all the pros around my part of the country use pro mix.

Ive never used a humidity dome for seedling and never had a problem. I also have a light breeze directly on them. Popped literally thousands of seeds. I think that instead of being dry they are too wet. Never used a heating pad on seedlings either. Pictures would help a lot.

the op might live in a dry reigon

Shivaskunk said:

Ive never used a humidity dome for seedling and never had a problem. I also have a light breeze directly on them. Popped literally thousands of seeds. I think that instead of being dry they are too wet. Never used a heating pad on seedlings either. Pictures would help a lot.

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I've planted two more bag seed(orange crush) and I've done one in soil (local seed starter mix w/no nutes) with mil's of water to hopefully avoid overwatering and one in new batch of coco mixed with perlite that was super flushed with 5.8 distilled cal/mag h20. I then used an attachment I made for my wet vac and sucked the excess water out the bottom of the 4" pot which mad the coco moist instead of saturated. I moved my fan from above and will have at ground level moving air around them and as for the humidity dome, are pop bottle tops ok and with or without cap on? I also have many zip locks baggies laying around waiting to be filled so can make a tent if better. Will take all y'all's input and start learning more from it and I greatly appreciate it and your time.

mrCRC420 said:

Keep your plants in the hum dome (or use sandwich bags). Don't blow air ON them, but around them. Get more light, a cfl an inch away from every plant. Heat mats aren't necessary and often cause issues. Overall Diagnosis: your seedlings are drying up.

Click to expand...

70's natureboy said:

I agree with mrcrc420, I don't think seedlings like a fan blowing on them. I always leave the dome on crooked for a couple days to gradually get them used to some air before taking it off altogether. I don't know much about coco because all the pros around my part of the country use pro mix.

Click to expand...

Shivaskunk said:

Ive never used a humidity dome for seedling and never had a problem. I also have a light breeze directly on them. Popped literally thousands of seeds. I think that instead of being dry they are too wet. Never used a heating pad on seedlings either. Pictures would help a lot.

Click to expand...

I agree with Shivaskunk, I always let my beans pop and they are in the sprout/veg cab with a 6" fan on hi blowin on them from sprout and they're fine, and I have a 26w 6500k about an 1-1/2 from the top of them, just had an OG bean pop 3 days ago..

MrMary said:

I've planted two more bag seed(orange crush) and I've done one in soil (local seed starter mix w/no nutes) with mil's of water to hopefully avoid overwatering and one in new batch of coco mixed with perlite that was super flushed with 5.8 distilled cal/mag h20. I then used an attachment I made for my wet vac and sucked the excess water out the bottom of the 4" pot which mad the coco moist instead of saturated. I moved my fan from above and will have at ground level moving air around them and as for the humidity dome, are pop bottle tops ok and with or without cap on? I also have many zip locks baggies laying around waiting to be filled so can make a tent if better. Will take all y'all's input and start learning more from it and I greatly appreciate it and your time.

Click to expand...

It sounds like you're over thinking/doing it, KISS is the best way...I was lucky, my tap water after being left out for 24 hours PHed at 6.6, with my nutes 6.7/.8...I was doing the SAME thing when I started, killing it w/love..lol....get some soil, stick a bean in a hole about 1/4 to 1/2 inch deep, keep moist (NOT SOAKED) with tap water left out for 24 hours to let chlorine evaporate viola bean sprouts...good luck man and welcome to RIU

If it keeps happening in different conditions of soil and watering, perhaps there is some material in or near your grow room there giving off toxic emissions.

i havn't found a problem caused by direct wind i have a cooler on my veg plants on low because it uses water to cool the air and humidifies at the same time with out it my veg cab would be about 26 % rh but my seedlings look strong and happy , i read threw this thing im not a pro .. but if maybe you could put a picture up ? people could help you alot easier

AimAim said:

Usually with damping off the stem will discolor and shrink in size at and above ground level. Here's kind of a classic pic of seedlings (not weed) that suffered from it. A greenhouse producers nightmare, it happens quick and is pretty much 100% fatal. Lost 12,000 tomato plants overnight once.

View attachment 2615895

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sprinkle a layer of charcoal crushed real fine and use garlic tea. no more damping off