Using hydrogen peroxide on seeds (bad technique?)
Did not work for me.
Planting up germinating seeds before they have fully sprouted
I am leaning this way too as they do better when an inch long.
Not enough warm grow space ( just got more heat mats)
Be careful with heat mats, too much of a good thing....
Underwatering for fear of killing them
Not too much not too little but too much is worse than too little
Magnesium deficiency (tried to treat as symptoms appeared)
I am using some greenhouse fertilizer in the water(very little) and it has micronutrients.
Using paper pots (3 ounce cups), see mold
Never use them.
Being gone during crucial time of growth ( friend watered)
Perhaps telling them to use spray bottle and mist them only
Weather: too many rainy days to get seedlings real sun
Seeds sprout in the dark but benefit from light almost immediately
Using aluminum pans ( maybe caused pH or nutritional deficiency)
No experience here.
Chlorine bleach soak and rinse twice in clean water is reported to enhance germination and reduce mold. Have not yet tried it. 
