Deflasked seedling die off

[Stray59]

Hello everyone and happy thanksgiving to the US members!
I have an issue - I have deflasked two flasks of seedlings and only a few (5-7) seedlings are alive; most dampened off. After the first batch died off and I had another flask that had to be moved out into the real world. After I planted the second, I decided to purchase Copper Soap, along with various other planting mediums in case I had better success with say rock wool over fine bark, coco fibers and spaghnum. I sprayed everything with copper soap, moved three 'strays' into the rock wool and two are fine, one is dead today. I have now lost about 2/3 of the last flask due to dampening off, so I am not getting ahead of it. Any suggestions will help. For those who have planted up flasks, what percentage of die-off do you consider "acceptable" or "expected"? I have increased air movement, sterilized everything, raised humidity, etc.
and, oh yeah, HELP - I have yet another flask on it's way! I really don't want to lose all of this one and am needing to 'catch on' to seedlings.

[Leafmite]

Our OS had a speaker who said that the key to having all the seedlings survive was to deflask to sterile medium. I think he boiled his mix before using it but I cannot be certain. He cut plastic soda bottles and covered the compote pots by fitting the cut part in the pots somehow (I think he sterilized these, too). When he deflasked, he left the flasking medium on the plants. He said he never lost any seedlings this way. I wish I knew more details but certainly someone else who has been successful can help. I have grown newly out of flask seedlings but never deflasked any so they've always been hardened a bit when I get them.

Sorry about your seedlings. I am newb and deflasked 2 flasks for the first time. Seedlings are 4 months old now and I lost just a couple because they were too small to begin with.
For compots I used the clay pots filled with bark on 2/3 and sphagnum moss at the top.
I keep them in propagation trays with clear domes.
To water I mist them and then leave domes off so the plants can dry out. Then I close the domes and check the moss every day. When it starts to get crusty at the top - I water again.
I didn't sterilize anything, just washed seedlings under warm tap water.
Here is how I did it:
Orchid log: Deflasking phalaenopsis first time

[Stray59]

Thanks to everyone that has responded already. Have the Holiday off, full of Ham and just browsing the board - a great day in my book!
As for my flasklings, I went to great lengths to sterilize everything, but NOT soil ny oversight. I had received the soil from a commercial grower who had just packaged some of his bulk up into zip-locks. I could kick myself as I ALWAYS dampen and microwave my medium if it is not sold as sterile. I also think the medium is too coarse for seedlings, but he said he used "one for all".
I have added a couple of pics to show the last of the seedling flats.
As you can see that I have planted into individual compartments. Maybe too early for this? I hear that compots may be the best initial planting. My compots have had a little more survival rate, about 1 in 7 lived, as opposed to 1 in 12 in the flats.
I have my seedlings in a converted jewelry display case that I had. I sterilized the case with an anti-microbial soap, have an air filter that supplies clean air into one end, a bowl of water with an aquarium air stone pumping humidity out (humidity ranges between 60 - 75%) and an additional small fan inside to make sure the air is never still. I leave the opposite end of the case open only enough to ventilate well, which ensures a positive air flow. The room stays a good temp between 68 - 75 degrees.
I really need to get the hang of this as I intend to start my own sales business.
Again - Any additional suggestions?

[Bloomin_Aussie]

Sterilising media is important. I saw significant improvement in survival rate after I started doing that.

I am told that using copper fungicides on seedlings will inhibit their growth so I would avoid using that. Sterilise the media, provide humidity with some air movement and you should be OK.

What were these seedlings by the way?

[Stray59]

Well Dan, the photos were of Slc. Final Touch 'Mendenhall'; I also lost all but about 5-7 of the first flask which was Pot. Samantha Duncan 'Orange Tart'; I am interested in breeding apricots, reds and b. digbyana v. fimbripetela; I have done some breeding and have somewhat of a dream orchid I am aiming toward crossing. Now to get my seedlings to live so I can afford to buy the stock plants I want. Ohhhh - the collecting never really stops does it?

[Rowangreen]

How quick are your's dying? I don't know if mine have been going long enough to count: I have 100% success so far with a batch of phals, paphs, Pabstia jugosa and an Angraecum. But it's been less than a month... And I am thinking of changing all the medium as I've got a couple of dodgy bits of medium/root.

[zxyqu]

Deflasking into a 60-75% humidity area is no sufficient. You slowly have to acclimate them to lower humidity over weeks. I use what orchieya is using. You need to keep them in near 100% humidity, but covering them for a brief while. Maybe 1 week later, you open the dome up just a a little and for a few hours, and recover it. Over a month or so you can slowly reduce that to 60% or higher. The plants and roots have been in 100% humidity for months/years, and the rapid removal of that can really make plants cull off. I'm also not a big fan of using any kind of fungi/bacteri/algicide. Just a little too much and you can really harm the plants as well. Just boil sphag (my preferred phal seedling media) and go.

[keithrs]

I have an approach that is a little different than most. I don't use any chemicals to kill pathogens. I use a product call Sub-Culture B. It's bacteria that helps protect the seedling from the bacteria that cause rot. After I remove the seedlings, I soak the in Sub-Culture, kelp, and a very light dose of fertilizer. Humidity is a big key to helping them survive. I recommend H to be 70-80% higher is ok. And any time you have high humidity you need strong air movement. Watch your watering. It's best if you can make some sorta greenhouse or grow tent and keep them in there for 6 months to a year.

The plants you have now should be tossed if they show any signs of rot along with the mix. The others should be dunked in a physan 20 treatment. Being that there Catt.'s, I would use LECA or similar to pot them in. That type of mix you have now is probably staying to wet. I would also suggest soaking the media in Sub-Culture after you sterilize it. If to use bleach or similar to sterilize the media then rinse it several times before soaking it in Sub-Culture as you'll kill any benefit the product has.

You don't have to use Sub-Culture B as there are other similar products on the market. I have purchased a "root pack" from draphwest on Ebay that is suppose to be very good. I have not used it as of yet.

[Stray59]

Rowan, zxyqu and Keithrs,
Thank you guys for the input. I have several options to work with now. I have changed my thinking about the overall approach and will be making some changes to my planting. Will keep you updated on the progress and what starts to work. Again, can't thank you enough for your assistance!
Steve