mother plants

You keep the mother plant in veg as long as you'd like to pull clones off of her. You can keep a mother plant for quite some time. I know people who have grown off the same mother plant for a year. I don't have enough space to consume all the clones my mothers produce so every now and then I flower off the mother, and start a new mother from one of her clones.

Second question is your choice. I'm more comfortable with soil, so I keep my mother plants in soil. Growing in a bb may speed up vegatative growth so if your going to be needing a high number clones more often the hydro may be the better choice.

No my 3 mother plants do not give off a very strong odor. I'm able to mask my plants in veg with deodarizers. In flower though they stink, and yeah I use filters for flowering. If you need a 100% stealth grow then yes a filter in veg will be a good idea as there is a slight odor especially when tending the garden