First Hydroponic Grow - Having Some Issues with Seedlings

Hey guys, I'm having some trouble with my seedlings. This is my first hydroponic grow so advice and constructive criticism is more than welcome! I tested the pH this morning and noticed it was 7.2, when it should be in the range of 5.5 - 6.5. I purchased some pH up and down and adjusted the pH (5.8 ) before watering this morning. Hopefully this was the problem that's causing the discoloration in the leaves due to nutrient lockout, but i'm only speculating.

Before anyone grills me for using a 600W HPS for seedlings, it's all I had laying around and I'm broke from buying university textbooks.

Indoor Grow:

Grow Medium: Coco Coir ( buffered with calcium and magnesium ) and 25% Perlite
Grow Room: 1.2 x 1.2 x 2.0m Grow Tent
Nutrients: Dutchmaster Gold A & B ( Veg and Flower )
Strains: Northern Lights & Big Bud
Lighting: 600W HPS
Fans: Small intake fan, large out take fan, oscillating fan

Grow Room:



Plant 1



Plant 2



Plant 3



Plant 4



Plant 5



Thanks a lot guys!

...seedlings can be tricky man, learning how to nurture them through this most delicate time in their life is a skill that often is only learned through many failures, i personally popped 30 my first time out and managed to kill them all within 2 weeks.

...anyway, i'd agree that your ph being that high might be the cause of your problem but i'd also suggest that they shouldn't need any nutrients at this stage and shouldn't need to be fed until maybe the third week after popplng.

...i'd also suggest that maybe another contributing factor is your use of such large pots for such small plants, i personally start my seeds in 9oz solo cups of coco and i don't up-pot until they are solidly established, ...the problem with using such big pots is that they stay wet too long so seedlings can suffer symptoms of over-watering.

...here you can see i sow my seeds directly into those coco cups and you'll note that i use a second clear cup taped above as a temporary humidity dome which is removed as soon as the seed emerges from the coco.



...and here they are with the hats removed, lol.



...and here are a few almost 2 weeks from popping and they are still too weak in the stem to be up-potted.



...and here's one about a week later and you can see how much thicker and more substantial the stem is above the cotyladons, ...this one is ready to be up-potted and it should be done so it is buried right up to those cotyladons because then roots will spring from that skinny portion of the stem, once buried.



...anyway, i'm assuming you're growing in some kind of drain to waste setup and as i grow in straight coco hempy-buckets, not everything i do would necessarily fit your situation.

...although i do grow with a single 600 as well, lol, ...i think my space is similar to yours as well but i'm old and lazy so never learn metric measurements, not precisely anyway, lol, so to me i look at a meter as if it were a yard so 1.2 meters is approx. 4ft? ...my space is a 4ft x 4ft closet.



...oh yeah, don't let yourself be so broke you can't afford to do this right and seedlings really are fragile and 600 watts is way too much light so either use your desk lamp with a CFL in it or go find a cheap bathroom vanity fixture like this one that only cost me $4.88 at my local discount builders supply house, ...full retail at Lowes or Home Depot or even Walmart maybe would be around $20.00.



...the bulbs can almost always be found in 4 packs for less than $10.00 and also almost always you can find a $3.00 instant rebate so that's 4 bulbs for about 5 or 6 bucks.

...here's a shot of one i was using over some clones without the Y splitters.



...and here's a shot of them over some DWC's i was running back then.





...anyway, the point is that a single 23watt CFL is all you need at this stage and for maybe the next 2 or 3 weeks too.

peace, bozo

justanotherbozo said:

...seedlings can be tricky man, learning how to nurture them through this most delicate time in their life is a skill that often is only learned through many failures, i personally popped 30 my first time out and managed to kill them all within 2 weeks.

...anyway, i'd agree that your ph being that high might be the cause of your problem but i'd also suggest that they shouldn't need any nutrients at this stage and shouldn't need to be fed until maybe the third week after popplng.

...i'd also suggest that maybe another contributing factor is your use of such large pots for such small plants, i personally start my seeds in 9oz solo cups of coco and i don't up-pot until they are solidly established, ...the problem with using such big pots is that they stay wet too long so seedlings can suffer symptoms of over-watering.

...here you can see i sow my seeds directly into those coco cups and you'll note that i use a second clear cup taped above as a temporary humidity dome which is removed as soon as the seed emerges from the coco.

...and here they are with the hats removed, lol.

...and here are a few almost 2 weeks from popping and they are still too weak in the stem to be up-potted.

...and here's one about a week later and you can see how much thicker and more substantial the stem is above the cotyladons, ...this one is ready to be up-potted and it should be done so it is buried right up to those cotyladons because then roots will spring from that skinny portion of the stem, once buried.

...anyway, i'm assuming you're growing in some kind of drain to waste setup and as i grow in straight coco hempy-buckets, not everything i do would necessarily fit your situation.

...although i do grow with a single 600 as well, lol, ...i think my space is similar to yours as well but i'm old and lazy so never learn metric measurements, not precisely anyway, lol, so to me i look at a meter as if it were a yard so 1.2 meters is approx. 4ft? ...my space is a 4ft x 4ft closet.

...oh yeah, don't let yourself be so broke you can't afford to do this right and seedlings really are fragile and 600 watts is way too much light so either use your desk lamp with a CFL in it or go find a cheap bathroom vanity fixture like this one that only cost me $4.88 at my local discount builders supply house, ...full retail at Lowes or Home Depot or even Walmart maybe would be around $20.00.

...the bulbs can almost always be found in 4 packs for less than $10.00 and also almost always you can find a $3.00 instant rebate so that's 4 bulbs for about 5 or 6 bucks.

...here's a shot of one i was using over some clones without the Y splitters.

...and here's a shot of them over some DWC's i was running back then.

...anyway, the point is that a single 23watt CFL is all you need at this stage and for maybe the next 2 or 3 weeks too.

peace, bozo

Click to expand...

Wow, thank you for taking the time to write such a great post! I'll definitely be buying CFL's tomorrow to put the seedlings under; I didn't realise they were so cheap. The humidity cup idea is also fantastic idea! Haha, it's reassuring to know that somebody else nuked a few of their seedlings their first try too!

As for the large pots with the seedlings, would you recommend just watering lightly around the base of the plant until she grows larger, or should I just move them back into smaller pots? I've noticed the pots are retaining quite a bit of water so I'll definitely slow down on my watering schedule.

Thanks again, bozo!

F.A Hayek said:

Wow, thank you for taking the time to write such a great post! I'll definitely be buying CFL's tomorrow to put the seedlings under; I didn't realise they were so cheap. The humidity cup idea is also fantastic idea! Haha, it's reassuring to know that somebody else nuked a few of their seedlings their first try too!

As for the large pots with the seedlings, would you recommend just watering lightly around the base of the plant until she grows larger? I've noticed the pots are retaining quite a bit of water so I'll definitely slow down on my watering schedule.

Thanks again, bozo!

Click to expand...

...you're welcome man and believe me, there will come a day when it's you helping some new comer, it'll be your turn to share the love.

and seedlings really are fragile for the first couple of weeks so some of your questions can only really be answered by and through experience, which is why i strongly advocate for new growers to learn their chops with free bagseeds, better to gain some cofidence with beans you don't care about so when you do start popping store-bought beans you'll know for sure you'll have a better than 50/50 chance most of your babies will survive, lol.

...as an example i just popped 6 beans 10 days ago and suffered only one loss 2 days ago, ...i tend to stress my plants a bit right from the beginning so in my garden only the strong survive, lol.

...and yeah, you'll need to water lightly so you can allow the pots to dry, this allows or maybe forces the roots to expand and search for moisture.

...in my own case and because i use small 'pots' i bottom water my seedlings for the first couple of weeks, i want the moisture coming up from the bottom so it drys out at the bottom last, the plan is to force them roots to reach downward, ...i grow in coco hempy-buckets which are a passive form of hydroponics with a mini reservoir at the bottom of each bucket so i want the roots to reach that res as soon as possible, lol.

good luck and remember that while this is new to you, it ain't new and if you really understand that and you then take it to the next level and realize that just about anything you can think to ask has almost certainly already been asked, many times, over the years, you can then become proactive and take charge of the speed of your progress.

...which is my point, not that you should not ask questions but rather that sometimes, hell most times, it is faster to hunt down the answers to the easy questions, ...the information you get will be more reliable as well, ...you certainly don't need conflicting information from other new people many of whom may know even less than you.

...so don't stop asking questions but also don't just sit and wait for answers, the answers are already here and the process of digging through old threads teach's us lessons we didn't realize we wanted to learn.

now it's off to bed for this old clown, lol.

peace, bozo

justanotherbozo said:

...you're welcome man and believe me, there will come a day when it's you helping some new comer, it'll be your turn to share the love.

and seedlings really are fragile for the first couple of weeks so some of your questions can only really be answered by and through experience, which is why i strongly advocate for new growers to learn their chops with free bagseeds, better to gain some cofidence with beans you don't care about so when you do start popping store-bought beans you'll know for sure you'll have a better than 50/50 chance most of your babies will survive, lol.

...as an example i just popped 6 beans 10 days ago and suffered only one loss 2 days ago, ...i tend to stress my plants a bit right from the beginning so in my garden only the strong survive, lol.

...and yeah, you'll need to water lightly so you can allow the pots to dry, this allows or maybe forces the roots to expand and search for moisture.

...in my own case and because i use small 'pots' i bottom water my seedlings for the first couple of weeks, i want the moisture coming up from the bottom so it drys out at the bottom last, the plan is to force them roots to reach downward, ...i grow in coco hempy-buckets which are a passive form of hydroponics with a mini reservoir at the bottom of each bucket so i want the roots to reach that res as soon as possible, lol.

good luck and remember that while this is new to you, it ain't new and if you really understand that and you then take it to the next level and realize that just about anything you can think to ask has almost certainly already been asked, many times, over the years, you can then become proactive and take charge of the speed of your progress.

...which is my point, not that you should not ask questions but rather that sometimes, hell most times, it is faster to hunt down the answers to the easy questions, ...the information you get will be more reliable as well, ...you certainly don't need conflicting information from other new people many of whom may know even less than you.

...so don't stop asking questions but also don't just sit and wait for answers, the answers are already here and the process of digging through old threads teach's us lessons we didn't realize we wanted to learn.

now it's off to bed for this old clown, lol.

peace, bozo

Click to expand...

Man, funnily enough I've never even seen bag seed! I guess I'm fortunate to have friends with quality product. Soaking the plants from the bottom up to let the top dry out first is a great idea! I'm definitely going to start doing that as of the next watering.

I noticed some nute burns on a few of the seedlings this morning, so I decided to flush them with pH'd ( 5.5 ) balanced water to ensure the burns didn't go any further and risk losing my plants. The Coco coir soiless mix is still taking a while to dry out seeing as the pots are so big, but I'm putting a reflector on my 600W HPS which will hopefully help to reflect more light and dry the Coco out faster. I'll be moving them over to CFL's afterwards.

Haha, yeah I totally understand where you're coming from. There's such a wealth of information it can be kind of overwhelming at times, but I'll be doing my best to sort through everything to make sure I form an objective opinion before asking anymore questions.

The plants seem to have responded really well to the flushing I did this morning! Their leaves were originally horizontal but now they're reaching up for the lights.

Hopefully we'll have a full recovery!