First time grower needs help on seedling problem

Hello everyone,
Ive got four seedling 12days old and ever thing was doing good untill I changed the lighting and/or gave them a tiny amount of MG. Now 2 of them have purple stocks and curled leaves and the other two are having problems standing up. The lighting I changed to is 2 26w cfl's daylight 6500 & 1 20w cfl warm. I had them 1inch from the plant and now I have them 3or 4inchs from the plant. Do you think my problem is the MG or the light change.

And for the ones that have a standing up problem I have had a fan on them since day one and The stem is strong it seems to be weak right at the ground

I'd say its the MG. They are too young to be giving nutes yet. You should wait until they have 5 sets of leaves before you fertilize again, and I would recommend using something other than MG. But thats just a personal preference of mine. I use it for all my vegetables and flowers, and they grow like nuts, but it just doesn't work that way with marijuana for some reason. At least for me anyhow.

Yeah I think its the mg also, what should I do flush the plants w/ extra water on the next watering?
Thanks

And does anyone know when to water the seedlings, its day 11 and there in 8 oz pots sooo....

You should only water when the soil is dry. So you won't necessarily be on any type of schedule. For me, it can be as much as every day, or as little as twice a week, depending on the rate which the plants take up the water, and how fast the soil drains out. For seedlings you want to be sure you don't give them too much or you will kill them. Usually when the top 2 inches of soil are dry, its safe to say they are pretty thirsty and would like a drink.

for the MG problem do you think I should flush the pots to get out all the MG? Or do you think they wil be fine?

Flsuh the pots. Definitely.

should I do it now or wait to the next time I water?