incandescent lights are useless for plant growth, it isn't the right kind of light spectrum. thats why your plants are tall and thin, they are growing to find a usable spectrum of light and cant find it. look into gettin some cfls. 6500k for veg. 2700k for flowering. the difference is 6500k have a blue spectrum, like the metal halides(mh). the blue spectrum is best for vegetative growth. 2700k have an orange/red spectrum/tint of light, like the high pressure sodium(hps). the orange/red tint is best for flowering. the light cycle for seedlings is best at 24/7. when using cfls, they should be within 2 inches of the plant. best thing to do when using cfls is to get 40w(two per plant), 80w(one per plant), 100w(good for 1 plant), 200w(good for 2 plants), or a 250w(good for 3 plants). if you have a shit load of smaller bulbs, like 26w, that will take a good bit of wiring, which is a hassle. also you should have 5000 lumens per square foot, for minimal stretching. you could use a 40w cfl to veg a plant to ablout 6inches. also when using cfls use the broadside of the bulb, it is the most lumenous. the downward tip is about 1/4 as lumenous. use the bold print to help you determine how many seedlings you would want to veg under each other type of light if you decide to go with cfl. but once they get past the 6inch mark, you would have to get another bulb with equal or greater watts for best growth and minimum stretching.
edit: ph for soil should be 6.2-6.8, ph for hydro should be slightly lower, 5.6-6.0