Grow Mediums What is killing my seeds???

I just did an experiment with the coco i had in the pot of one of my dead seedling. I put a cupful in a solo cup and cut holes in the botom. Chceked PPM and PH before and after...

Starting water= 7.4ph 142 ppm

Run off= 7.3ph 302ppm

Would that be causing my seedlings to die?
 
That's 160 mystery ppm's. Not much unless it's salt.
 
Ugh..I have 2 more seeds germinating now...I don't know what to do here....Is there anyway to pretreat the coco to encourage rooting? Could that 160 mystery ppm's be causing my seedlings to die in less than a week from sprouting?
 
I just did an experiment with the coco i had in the pot of one of my dead seedling. I put a cupful in a solo cup and cut holes in the botom. Chceked PPM and PH before and after...

Starting water= 7.4ph 142 ppm

Run off= 7.3ph 302ppm

Would that be causing my seedlings to die?

Hi slimjim, what ph is the water that you normally use, when I did my hemp you grows, I kept ph between 5.6 and went up to 5.8-6.0 in heavy flower. I assume coco would be the same.

I apologise if you are watering at a ph in the 5.5-6.0 range, just unsure after reading above. If your ph is normally this high, yes it would kill your seedlings.

Also runoff seems high from just water, I would say pre rinsing is needed.

Ugh..I have 2 more seeds germinating now...I don't know what to do here....Is there anyway to pretreat the coco to encourage rooting? Could that 160 mystery ppm's be causing my seedlings to die in less than a week from sprouting?

Do remember reading a couple of grow journals in the past where coco growers have pre washed, then soaked coco in cal/ mag prior to use. If I remember correctly coco finds it hard to hold on to minerals due to it being an inert medium. Like I said have never used, only perlight in hempy ( used to heavily pre wash perlight, then leave to soak in ph 5.5 water for 24 hours) so would advise having a read on some coco threads.

Good luck.
 
Hi slimjim, what ph is the water that you normally use, when I did my hemp you grows, I kept ph between 5.6 and went up to 5.8-6.0 in heavy flower. I assume coco would be the same.

I apologise if you are watering at a ph in the 5.5-6.0 range, just unsure after reading above. If your ph is normally this high, yes it would kill your seedlings.

Also runoff seems high from just water, I would say pre rinsing is needed.



Do remember reading a couple of grow journals in the past where coco growers have pre washed, then soaked coco in cal/ mag prior to use. If I remember correctly coco finds it hard to hold on to minerals due to it being an inert medium. Like I said have never used, only perlight in hempy ( used to heavily pre wash perlight, then leave to soak in ph 5.5 water for 24 hours) so would advise having a read on some coco threads.

Good luck.

7.4PH 130-140ppm range is the water i use to expand the coco bricks. After they are expanded I add perlite to the moist expanded coco and then plant my germinated seeds. They usually sprout a few days later and then die within a few days if they make it totally out of the coco. Last 2 seeds wilted when they were about to break through the coco, and I didnt even water them yet.

I normally water/feed my girls around 6.0 PH through the whole grow...

I guess i could rinse the coco until I get matching PH/ppm??

Again, I cant thank all of you enough!! With so much mis-information out there, it's good to come to a place where everyone is so positive and helpful...thank you.
 
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Rinse your coco first. I use just regular Ph'd tap water after it runs clear then pre-charge your coco with a mild nute mix no more than .80Ec this should include a cal/mag and a root developer along with your grow fert.

I do the above at the same time I place bean in water. In 24 hours the bean has cracked and it gets place directly into the coco then I place a shot glass over the seed. During this time I do not need to water, when she breaks the surface I remove the glass and let it do its thing. For the most part I don't have to water for a few more days after she sprouted. But If i do I use the same feed as above @.80Ec and draw a ring around the seedling I do this for two weeks upping the amount of water and Ec. I will go 2 days without feeding after the first full 7 days. on or about the 14th day I Feed till runoff let it dry 2 days and then I start dripping till runoff. By now I am between 1.1 and 1.3 EC. I start the drip at twice a day and escalate based on how she looks until I reach 6 times per day @ 1.3 Ec.
 
Ph 7.4 should be fine for rinsing, but consider 5.5 - 5.7 for soaking, adding nutes.

ppm seems fine.

Perlight generally has a high ph so needs a really good rinse and pre soak in ph corrected water. First 4 hempy buckets I rushed the rinse but did pre soak for a night, this still caused me problems with a higher ph than what I wanted for the first 2 weeks or so.

I would definitely rinse the coco and perlight well with any water, then possibly think about a pre soak in some ph corrected water for your perlight and possibly pretreat with cal mag and maybe nutes, seeing as none are present in the coco unlike soil.
Like I have said, I have not used coco, but as it is hydro, like hempy grows, it does seem it will need a weak pre charge to get your seedlings going.
I would still recommend checking out what the expert coco growers do on here before starting any more seeds off. The better the start for the young ones, the better grown plant you will have. In fact I'm curious myself about pre charging coco, so will go and have a read myself.
Good luck bro.
 
Rinse your coco first. I use just regular Ph'd tap water after it runs clear then pre-charge your coco with a mild nute mix no more than .80Ec this should include a cal/mag and a root developer along with your grow fert.

I do the above at the same time I place bean in water. In 24 hours the bean has cracked and it gets place directly into the coco then I place a shot glass over the seed. During this time I do not need to water, when she breaks the surface I remove the glass and let it do its thing. For the most part I don't have to water for a few more days after she sprouted. But If i do I use the same feed as above @.80Ec and draw a ring around the seedling I do this for two weeks upping the amount of water and Ec. I will go 2 days without feeding after the first full 7 days. on or about the 14th day I Feed till runoff let it dry 2 days and then I start dripping till runoff. By now I am between 1.1 and 1.3 EC. I start the drip at twice a day and escalate based on how she looks until I reach 6 times per day @ 1.3 Ec.

Nice advice mate, what I love about afn, there's such a wide knowledge base always happy to help out a fellow grower. Happy growing.
 
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