I personally don't recommend indoor gardening. Mold is toxic to humans. Some molds are deadly toxic. You never want to encourage mold growth in your indoor environment. It's not worth the risk. I have a freind who is the foremsot leading expert in indoor environemts as they relate to health (tenored proffesor/doctor of indoor environemntal design). He emphatically tells people to stay away from growing situations like this due to a significant risk of starting toxic mold within your home. Once started, it is near impossible to reign in without very costly abatement measures.
Wait til you can grow it outdoors and yes, by all means flash freeze lots to stor up in ice cube sized amounts for use over the winter season.
You ususally get one good cutting and one small cutting before having to reseed a new batch. You use several trays and rotate them (stagger start times) so you always have a new, fresh batch.
As far as mineralization it is best to use the ocean water. Yes Colloidal Silver would be good for you and the plant but make your own so it is much less costly.