Can't Get Out of the Starting Gate

I raised quite a lot of cannabis plants in the old days, always on hydro with rock wool and hydroton. I became friends via e-mail with a very well-known seed merchant and grew perhaps 50 of his varieties, cross-bred them, cloned them, cloned the clones, and also produced viable seed from them. Toward the very end of all that, I thought that it had become more difficult to get the flowering plants to finish properly, like my house might be tired of growing them. Now some 15 years later when I try to get my new auto flower seedlings to grow, they do sprout normally and look perfect through the first true leaves, and then death creeps in and kills them all, 32 of them so far, all premium seeds from ILGM, and other vendors. I have all the equipment to go from start to finish, using 1.5 rock wool cubes after germination, humidity domes (all sizes), heat mat (so long as the temp doesn’t skyrocket), all under T5 fluorescents in the propagation tent. I have fancy new LED lights to veg and flower. Two of my candidates progressed enough to warrant advancing to 6" net pots with grow stones surrounding the rock wool, hoping to start DWC in the new Gorilla Growtent, but then after trying valiantly they collapsed and died too. Usually they just stop in the little cubes without making much root at all. They ignore Rapid Start and Root Builder and rarely use much nutrient unless I peel the paper off of the rock wool for transpiration and leave off the domes. I have recently become aware that incorporating food grade hydrogen peroxide may help if I am experiencing “Sick House” syndrome. I bought many of the houseplants NASA used to clean up the air in the Space Station (Peace Lily, Snake Plant, Dracaenas, etc.). I have carbon filters and packets placed strategically in the growing area. I had the carpet cleaned and added an HVAC scrubber to the ventilation system when it was cleaned. Maybe I just grew more than my share of cannabis in the old days. As humiliating as all this is for me, I am even trying growing them outdoors in soil, bypassing the house altogether for now, hoping I can somehow quit killing them before I run out of these excellent seeds. Even though I can boast of no positive results so far, at the very least it is a FASCINATING hobby, and any and all suggestions are welcome.

Have u disinfected ALL and I mean ALL of ur tools and equipment associated with growing? Alot of people have bacteria and fungus issue with rockwool cubes too, they tend to not dry proper and overwatering causes festering bateria.
Maybe time to try some different methods??

Thanks for your reply. Different methods do seem to be in order as I become less enthusiastic about the rockwool method. I do use bleach and rubbing alcohol regularly in the household, and perhaps now H2O2 as well, but so far very little other cleanup has been necessary so far as I can tell, though I am ready and willing to clean it all, somewhat worried that bringing in dirt from outdoors will introduce contaminants that otherwise might be avoided. Outgassing from the new grow tents was considered as a possible culprit. All of the supplies (nutrient, medium, pots, etc.) are brand new as well.

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H2o2 is often used to disinfect too. I also use bleach, Mr Clean or Pine Sol.
I use Jiffy peat pucks for my germinating. Dropped the rock wool cubes 15 years ago.

This morning I thought about shopping for Jiffy pucks for the outdoor soil experiment. Might give it a try.

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I don’t have any problems with the rock wool. You need an air space between the rock wool and the water to keep them from damping off. I use H2O2 and star San for sanitizing. I use to have problems with root rot, until we finally figured out what was going on and bought a water chiller.

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I use the Jiffys for my clones too. They seem to do the trick
Clones r in the covered containers in peat pucks. And only a few bucks for 36 of them.
All those seeds r in pucks too but have dirt over them now

What type of system are you using? 5 gal buckets? Anything I can do to help, just tag me. As far as soil goes, the only thing I know is it’s good for covering bodies.


Growing in dirt is also foreign to me. I have the 5 gallon or 3 gallon buckets for DWC, but it seems pointless to set up all that when I can’t even get seedlings more than a couple of inches tall. My old veg system was ebb and flow and then drip rings in 5 gallon buckets for flowering. Thanks for your help.

Do you get bleach around your growing equipment? My understanding is that it’s best to keep bleach out of grow spaces and equipment.

You may have several issues, or just 1 issue that could be compounding into several different problems. Seedlings not producing roots for instance… too much water can hamper root production. If the plant stem can take up water on it’s own the plant won’t focus a lot of energy on root production. When amount of moisture in medium is kept minimal, the roots will expand looking for water. Another problem with too much water is stem rot or damping off. Just some examples, and may not be true at all in your case. But something easily corrected can be a real pain to deal with.


Thanks for your input, and I do agree with all of your comments. In addition to using bleach as a cleaner I was advised by the local hydro shop to use CLR (calcium, lime, rust) to remove nasty buildup in between grows, and I have used that on flats, domes, etc. Too much water initially was also my first suspicion, and my efforts have been to keep that reasonable. Your suggestions do seem to be on point.


Star Sans Sanitizer 4 oz.

It comes in various sizes, but one ounce makes 5gal.

Bleach is the best to sanitize equipment 1z per 5 gallon is sufficient to soak and kill everything including fungal spores.

As for germinating, anything that holds too much water will breed bacteria and fungi. I will be moving to rapid rooters for my next round. They are pH balanced and made specifically to not hold as much water as rockwool.

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Perhaps I have relied on the bleach too much or used in too heavily (not diluted enough). I know that it does react badly with other cleaners like ammonia, vinegar, and I wonder too about its interaction with H2O2. Am checking out the Star Sans. God knows I give Amazon enough business. Without these suggestions I would feel like I’m fighting a battle with no weapons.

Star Sans Sanitizer and Rapid Rooters are on their way


Awsome I have great success with rapid rooters. Just be careful not to really soak them because they grow green on them quite easy in my experience. Just drop the seed in, RIP a little piece off the side of the rapid rooter and block the hole. Then add some distilled water and put in the tray with dome. I don’t usually water again either and It 99% never fails, they are my go 2. They are a little tougher for cloning though, but I’ve managed to get some cuttings to root. Hope you solve your problems!

Like I said I’m new but any time I want to cut stem I scrub my scissors it’s unreal how stuff from plants build up, then I sanitize in alcohol so far no problems. What type lighting do you use and how close to plants and I was told,someone correct me if I’m wrong, When I water I water till I get water running out drain holes. I’ll send you some pics in morning it’s working for me. I’m trying to get better with nutes and 1st grow I defoliated cause that’s what I was told now I’ve learned not to cut anything.

Thanks Noctis420 for the tips with rapid rooters, and I did just stock up on distilled water.Then his morning I read a little about chemical reactions. Like you Rena, I like to use rubbing alcohol on some of my gardening tools, say when the hard seed helmet gets stuck on a new seedling’s radical. I might just do “surgery” to free up the cotyledons with a small probe wiped with alcohol. But the propagation trays and humidity domes I use are usually cleaned with bleach, and Bleach + Rubbing alcohol =Chloroform…OUCH. So drbrn32’s warning about bleach in the growing area indeed cuts to the quick. Then Hydrogen Peroxide, H2O2 is produced by the vent duct scrubbers I recently installed in the HVAC system here before purchasing all my new grow toys. I also ordered a gallon of food grade 35% H202 online as I see many growers use this even in their nutrient solutions. However I also like to use vinegar sometimes to clean, and even drink that (Apple Cider Vinegar) every day to help with weight loss. Well H2O2 + Vinegar= Paracetic acid, a potentially toxic irritant, and WORSE, Bleach+Vinegar=Chlorine Gas,which we all try to eliminate from tap water by letting it sit out for a while before using. So then three of my favorite cleaning agents for my grow room can form toxic or even deadly gases. While I am not a scientist, it is becoming clearer to me that my best attempts to keep the growing area clean may be at the ROOT (he-he) of the problem. Thanks dbrn32 for the heads-up about bleach–I still have some very mighty seeds to help me figure it all out, but if I finally kill all of those too, I hear there are more for sale at ILGM. Back to the drawing board.


White Widows and Jack Herers

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I blew up the pic. Those seedlings are damping off.