First seeds sown 11/2/2012

I have done best in a 50/50 mix of propagation sand & seedling soil. The seeds do poorly in pure sand.

I'm beginning to take the lid off and let the cactus dry out a bit so I can fert them. If I don't let them dry out I wont be able to fert them.

Is 6 months too little to take their lids off and keep it off?

I have some sealed in plastic bags that I planted in December, and in fact, I have read a number of people stating that as long as the seedlings have room to grow, and enough moisture, that they have kept them in sealed bags for over 2 years! Early on I found out that I like bags better, because some seedlings grow taller then the lids allow for, but will still benefit from the high humidity & warmth that they can get in a sealed environment.

So they will grow faster in higher humidity rather than lower humidity for the first 2 years?
Hopefully they start growing faster now because at the moment they haven't really done much in a while... I think lack of nutes.
When the warmer weather comes I'll take them outside (still in their baggies) and give them more sun.
They are currently growing a bit leggy for my liking although the ariocarpus are filling out a little bit.

I have a number of seedlings still in bags after nearly a year, and they are growing great. The only ones that I have had to pull from the humidity are the ones that have grown too tall, or too tightly packed together.