Damping off or Nutrient burn or deficiency? Please help

Having some trouble with some seedlings. There are several affected plants.

Currently in 5" pots:
peat
coco coir
perlite
vermiculite
high nitrogen bat guano - small amount
kelp powder- small amount
worm castings- small amount
azomite- small amount

Plants are 1 month old
Watered sparingly, soil is not soggy though it is a bit dense - possibly too much vermiculite

I lost 16 seedlings to damping off - had the humidifier on too high - dumb mistake
Now RH is at 45% and temp is around 75F
All plants were given the same soil

EM-1 given by spray bottle, highly diluted, a few times
No other liquid nutrients given

Plants in the pics:
Critical Purple Kush - tall plant with damping off type symptoms
Bagseed strain - brown tips and brown lower leaves
Strawberry banana - pale, cal/mag deficiency?

Thanks for your help!

Welcome to RIU

Update:
The stem on the taller one is broken, starting to fall over in the grow room. Looks like it was fusarium after all.

Anyone have experience pretreating soil with compost tea to prevent fusarium?

aqua-marine said:

Update:
The stem on the taller one is broken, starting to fall over in the grow room. Looks like it was fusarium after all.

Anyone have experience pretreating soil with compost tea to prevent fusarium?

Click to expand...

One problem is calcium def which affects the stems too, and maybe a potas problem too.
That's my noob opinion.

aqua-marine said:

Update:
The stem on the taller one is broken, starting to fall over in the grow room. Looks like it was fusarium after all.

Anyone have experience pretreating soil with compost tea to prevent fusarium?

Click to expand...

Generally caused by over watering. I use beneficials to prevent fusarium (Great White in my case). A compost tea should work fine too.