Newly Bought Grow Light Questions

[Vesper]

Today I bought 2 fluorescent light tubes labelled as "plant and aquarium, wide spectrum fluorescent lamp" There are 48 inches long, 40 watt, and the light output says 1900 lumens. I plan to hang them above my plants. Now I know that some plants won't thrive under high lighting such as my orchids and ferns, but there are some plants and seeds that I'm planning to put under the lights so I will list them.
Plants:

Jade
Lithops
Ornamental Pepper seedlings (they are about 1 1/2 inches high)
Yucca seedlings (About 4 inches high)
christmas cactus

Some seeds I have that I want to germinate:

Wild Iris
Peacock Flower
Bird of Paradise
Lavendar
Mixed Cacti seeds
chives, parsely, oregano, cilantro
strawberry

Are there any particular rules that come with using grow lights? I am unsure about how close I should have the grow lights hanging above my plants/seedlings. I am also unsure about how long to leave the lights on before turning them off and when to turn them back on again? I know that some of the seeds that I listed need to be in the dark in order to germinate, but will all of the seeds be ok to place under the grow lights once they have germinated? Any suggestions would be greatly appeciated

[rainbowgardener]

I just noticed that you never got a response to this post, so I thought I'd make a stab at it.

I haven't paid a lot of attention to lumens and all that. What I have is regular fluorescent tubes in shop light fixtures. I start hundreds of plants from seed every year under them. If you are just germinating your seeds and growing them out to good transplant size that is fine. If you are keeping the plants permanently under lights and especially if you want to produce harvestable fruits, you probably have to be a bit more picky.

Re germinating the seeds. Since I have a mixture of needs light to germinate and doesn't need light in the one tray that is currently sitting under my lights, the lights are on. The needs light seeds are on top of the soil under the light, the doesn't need lights ones are (slightly) buried, so they are in the dark, under the soil.

Once the seedlings have sprouted, you want your lights to be just a few inches over the seedlings (hung so that they can be raised as the plants grow). It's usually recommended that they be on 16 hrs a day, which is what I do.

[Halfway]

It is my understanding after researching this very issue is to use "cool white" bulbs as the base and supplement with one "soft white" if the fixture holds 2 bulbs. Do NOT use both "soft "white".

On the higher end shop light bulbs, use "daylight 6500k" as opposed to "fullspectrum". The light the plants need are in the "daylight 6500k" range.

Refraining from positing a link, try googling indoor garden lighting.

[spaceace]

I've successfully grown and harvested tomatoes using a 250watt HPS in a bat-wing(I think that's the right name) reflector. they were fuzzy peach tomatoes and I got about 15lbs from 2 plants.