New to Hydroponics. Some Questions

Hi all. I'm planning on trying hydroponics for my next grow. I was thinking a 4x8 ebb and flow tray with I guess the 100 gallon reservoir. My questions are,

1.) Is it a good idea to use the ebb and flow technique? The one thing I worry about is the roots.
Is 10-15 minute water run sufficient enough to keep my roots moist and not dry until the next run? (I plan to run 4 times a day, 2 on, 2 off) Is a 100 gallon reservoir necessary? Does it take 100 gallons to fill it to the top?

2.) Is a 100 gallon reservoir necessary? Does it take 100 gallons to fill it to the top?

3.) Root mass, I plan on having a decent sized family probably 4 across, 8 up. 30 give or take I'd say. There isn't anything wrong with having them just sitting at the bottom of the tray intertwining with each other, Is there?

4.) Last is, how often would you say you refill your nutrients into the reservoir? My temps are usually around 70-77 and I don't think I'll see too much evaporation from heat.

Thanks ahead.

1.) It sure isn't a bad idea, although the HUGE res size has always turned me off to this Idea. As for roots, I think they will need watering more often with ebb and flow but you should look into some successful ebb and flow journals, do not take my word for it.

2.) depends on how high you have to water go. figure out the aria that the flooded water is to take up in inches^3 and divide it by 231 (inches^3 in a gallon) to find gallons needed.

3.) No there isn't anything wrong with that.

4.) depends on the res size, some people with big reservoirs don't change them at all during a grow, but most people will tell you to change the res every 2 weeks to avoid issues. I change my res every week because its pretty small.

What about seedlings and ebb and flow? Would I have to adjust the rockwool as it grows or just let it sit exactly on top of the water level and let the roots come down? I'm thinking I might just go with top drip feed over ebb and flow but the ease of ebb and flow attracts me and I always loved to develop film in darkrooms with an ebb and flow table.