Hi The plants can be anywhere from 3 foot to five foot tall depending on the variety. Most of the ones I have grown needed to be staked and tied(like a tomatoe) I think they would be a bit large for aquariums, but I guess you could try planting 2 plants in an aquarium. It would be an interesting experiment. I am hoping to maybe "borrow" the greenhouses near us that are not being used to grow some this winter. THere was nothing planted in them this winter ...just full of very tall, dried up grasses. That would be an experiment just to be able to harvest tops for tincture.(..without bees or some sort of polinator, there will be no beans). That would be a consideration for you also...growing indoors could produce plants (and tops to harvest & dry for tincture) but no beans. It depends what you wish to produce wether it is worth trying it.
We are still in drought conditions here, but, I have transplanted 100 asparagus plants in a very long row, and still have baby plants left from starting them from seed around Easter outside in old window cold frames. Just started a seed bed with alot of echinacea, also brocoli, cabbage, brussel sprouts, cauliflour, and herb seeds. This weekend , I hope to plant a couple pounds of fava seeds in the garden area my 85 yr old dad just plowed up a couple of weeks ago...he's amazing! I have just strained off my first batch of fava tincture (what I am using for my symptoms) It makes me feel better to know that there is a 6 month or more supply of it on hand now. The supply was getting pretty low.
The long row of Sunflowers are amazing & full of bees. Wish you all could see them.
God is good and supplys our needs.....Blessings to you all