Help with sick plants?

[wolfie198323]

Hi. I've been growing special queen by RQS for the past 5-6 weeks. The plants were looking great at about 8-10 inches tall, and I was planning starting flowering in two weeks or so. About 4 days ago I noticed some spotting on the leaves. After some research I thought it was either a calcium or magnesium issue, so I changed out the reservoir and added cal/mag plus from botanicare. (Otherwise I'm ½ strength of the full foxfarm hydro lineup.) I also used the cal/mag as a light foliar spray. The next day the problem seemed to worst, not getting better. So after more research I thought maybe root rot was the issue. (Kinda hope I'm wrong) So last night I add 1 TSP/gal of 35% H2O2, and did it once again 12-14 hours later. I was planning on adding ½ tsp/gal later tonight when I get off work as well. (The issue didn't "seem" to get worst overnight) I have a bottle of AM hydro's companion (beneficial microbes) I was going to add in 2-3 days when the H2O2 dissipates. I also order some Botanicare Aquashield that should be here Saturday or Monday. I was just wondering if anyone could tell me if I'm approaching this the correct way? Also the plants are in a 2'4' grow tent with a 400 watt MH in a cool tube with a 440 CFM fan. In two weeks I was planning on throwing them in a 4'X4' tent with a 1000 watt HPS. I couldn't figure out how upload pics on the forum directly, so i have added URL's

Thanks!

 

[PlanetJ]

I have a similar issue .. most likely nuteburn if I'd have to call it.

 

[wolfie198323]

I don't think it's a nute burn. I'm using 1/2 strength of the full line of fax farm hydro nutes. (Last res change i only went 1/3 strength) plus the cal/mag i added. Last week the roots were really white, now their yellowing. Ive uploaded some pics i just took. The plants themselves dont seem much worst today. (but i have foliar fed them the past 3 days.) The roots look worst though...They were being watered for 15 min every hour, and after then after i noticed the root issue i cut back to every 4 hours to let them dry out, and i thought i had killed the plants when i got home from work (quite wilted) but after an hour of letting the pump run, they bounced back up. The pump now kicks on every 90 min.

 

[PlanetJ]

Nutrients in my soil are ment for seedlings, and I added half strenght pretty mild fertilizer (12-10-18 NPK) .. I only have it at the lowest leafs, and it's not getting worse. If it would be a deficiancy, this would be a progressive stage, and you would have to have missed everything leading up to this point .. or so logic says.. unless it's nuteburn.

(same plant, looks like the same issue to me, yet less bad)
https://www.420magazine.com/gallery/data/500/20140402_184047.jpg
https://www.420magazine.com/gallery/data/500/20140402_184420.jpg

I have 0 experience with hydro tho .. and am a firsttime grower .. so I'll shutup and learn from here on

 

[Fuzzy Duck]

Took a look at pic's...

No nutrient burn if ya running at 1'2 strength.

With the first few pic's seen it seemed Ca-calcium def ? could be water related whether its soft or R/O water ?


But further pic's appeared more P-phosphorus def related !

I suspect this is more likely due to under feeding & that you need to increase your nutrient dosage too counter the problem

 

[wolfie198323]

@fuzzy, I hope your right. i just doubled up on the nutes. (now running at 2/3 of the recommended levels) Every post I've read states FF runs hot, and to only run half strength. I was so worried about it being a disolved O2 issue, so i ended up ordering this commercial air pump.
Hydrofarm Aapa70l commercial Hydroponics Aquarium Pond Air Pump 8 Outlet 70 LPM | eBay
The extra O2 and beneficials can't hurt....

 

[Fuzzy Duck]

@Fuzzy, I hope your right. i just doubled up on the nutes. (now running at 2/3 of the recommended levels) Every post I've read states FF runs hot, and to only run half strength. I was so worried about it being a disolved O2 issue, so i ended up ordering this commercial air pump.
Hydrofarm Aapa70l-commercial Hydroponics Aquarium Pond Air Pump 8 Outlet 70 LPM | eBay
The extra O2 and beneficials can't hurt....

FF or fox farm running hot is mainly related to one of their compost being preloaded with nutrients.

The liquid nutrients by fox farm should be just fine tho... how ever !


Most hydroponic style growers using a res adjust their nutrient strength via an EC measurement starts of low for young plants & gradually increase's through the stages of plant development.

EC - electrical conductivity of nutrient solution... basically means more nutrients in solution increase's EC level !

Small young plants don't need lots of nutrients but as the plant grows bigger & flowers etc a greater amount of nutrients are required to support good plant growth/health

 

[Fuzzy Duck]

I don't think it's a nute burn. I'm using 1/2 strength of the full line of fax farm hydro nutes. (Last res change i only went 1/3 strength) plus the cal/mag i added. Last week the roots were really white, now their yellowing. Ive uploaded some pics i just took. The plants themselves dont seem much worst today. (but i have foliar fed them the past 3 days.) The roots look worst though...They were being watered for 15 min every hour, and after then after i noticed the root issue i cut back to every 4 hours to let them dry out, and i thought i had killed the plants when i got home from work (quite wilted) but after an hour of letting the pump run, they bounced back up. The pump now kicks on every 90 min.

Check the temp of your res could be root rot, if they go slimy then that is rot...


62-68°F (17-20°C). Above 72°F (21°C) and dissolved oxygen (DO) dips too low. Below 60°F (16°C) and plants tend to slow their metabolism as they "think" the season is changing.

 

[wolfie198323]

The temp in the res has been in the high 70's to low 80's. (It's been warming up here) I thought since it was a flood and drain system the res temp wouldn't be a big deal, like it would be in a DWC system. I lowered the water temp to the 50's range. I did't even have a bubbler in the system, thinking 3/4 of the time the roots would be exposed to air anyways. I bought a TDS meter when i started. When i started seeing these issues my PPM were in the low 600's, and i brought it up to around 1050 last night. (plus im still doing a light daily foliar feeding every day w/ humboldt county's full line of supplements, and a very low does of the FF nutes) After 3 days, I'm finally starting to see some new growth The roots aren't slimy, but they are brown, and a little crispy. They had been a nice white color up until recently. Hopefully this issue only sets them back a week or so.
Is vegging them in a 2'x4' till their about 18 inches, (I have 10 plants in there) then moving them to a 4'x4' tent a good idea, or should i move them over as soon as they look like they have recovered?

Thanks for the help, Fuzzy!

 

[Fuzzy Duck]

Not seen a flood & drain system like that before ?

Seen similar systems as NFT some more fancy ones had spray nozzles in...

Perhaps you might want to include some extra flood & drain periods with in the cycle to help stop the roots drying out ?


I think you will find suitable results now you have increased the nutrients & may have too go as high as 1800 PPM by mid flowering, you can find rough guides etc but take them as a rule of the thumb as some strains differ in nutrient requirements either being sensitive or more hungry... ye a slight learning curve for each strain !

Myself i read my plants for signs of deficiencies & once identified adjust nutrients.

Over the couple years here at the forums & growing for my own needs i've noticed a common pattern of deficiencies mainly NPK through the life cycle of the plant...

I would certainly watch for P - phosphorus & K - potassium def in early to mid flowering tho as most bloom nutrients don't give enough & that you may have to supplement with a P/K boost, becareful with P/K boost over double figures etc like 13/14 etc they can spike the EC/PPM up & you may get a little nutrient burn... just got to play around a little with measurements.

Always back up grow/bloom nutrients with a micro nutrient solution with hydro or any other type of grow style its just a wise precaution.



Mmm vegging in till 18 inches tall !


You need to think about stretch during flowering depending on strain genetics if seed was gained from a seed bank it should of stated growth height on average from short, medium or tall that should give a little hint & some times after searching for strain reviews you might find some more details ?

On average stretch in flowering occurs for the first 2 to 3 weeks you might expect 1/2 inch to 2 inch of growth a day once in 12/12 lighting

This might test height limitations of grow area once you have factored size of pots/system used for growing, hood size & suitable hanging distance of bulb used... what ever space left is your limit on average for plant height !


Some methods are available to control plant height tho !


2'x4' might be a bit small for flowering 10 plants as they may bush out a little more and that size area more likely suitable for a SoG style type of grow with those numbers.

Moving into a 4'x4' will allow more space for em to bush out, increase air flow around the plants & improving over light penetration to plant canopy



At the moment i would honestly think about how long you are going to veg for & possible size of plants once stretch has happened ?

I got a funny feeling ya in grow tent which i suspect has a max height of 200cm/2m or 6 foot.


Present system used for vegging i guess to be 40cm to 50cm tall... i'm not to sure what ya using for flowering yet ?

 

[wolfie198323]

I bought some "special queen" seeds from a seed bank. They were some of the cheapest, and i figured they'd be best while im still learning. They are considered tall plants with a 7-8 week flowering time, and 500 grams per square meter.
The 4x4 tent i purchased for flowering is 6.5 feet tall. I figured if they stayed under 3'-3'6" feet tall i should be okay. I also purchased a 1,000 watt light for that tent. (compared to the 400 watt light in the 2x4 tent) Both rooms have cool tubes. With the 400 watter. I can touch the glass and its not uncomfortable to the touch. I was wondering if i could daisy chain the two lights with the 440 CFM fan i purchased, or should i buy a 2nd unit for the 1000 watt light? Here's what the flowering room looks like so far.

It's still a work in process. I need circulating fans, and one more reservoir. (I figured running two reservoirs gave me more options, and allowed me to build it lower to the ground. Also using PVC pipe was 1/3 the cost of using the vinyl fence posts i used in the grow room) I went ahead and made 20 spaces for net cups on this grow table. For now i can use every other space, but i was thinking about cloning down the line, and only using 6-8 inch tall clones in every slot.

On a side note, how many watts are you putting on a single breaker? Or, how many would be safe? I have a standard 15 amp breaker in this spare room. (The same breaker is used in a bathroom as well) If i start cloning i could be drawing 2,000+ out of this one room, maybe more if a small ac is needed in the summer....

 

[Fuzzy Duck]

500g per M2 that is related to SOG method what they don't tell you is how many plants achieved that figure !

Could be any where from 12 to 36 plants & on average 20 to 25 plants per M2 totally different grow style to achieve those yields... most of that will be with a 600w hps. Kind of got a feeling ya setting up for that from pic of grow room... nice DIY job


Tall strain ah with 7/8 week flowering more likely a hybrid expect it to double to triple its size from veg height once flipped to flowering timing... bit hard to say depending on dominate genetics ?



You could daisy chain it but would suggest a bigger fan for the job to be on the safe side... but you could always do a dry run once all set up to see what temps do etc...