Shadow Lord
Dark Lord
MystagogueProbably a lot of insects would be used for meat.
Shadow LordWell, that ends space travel for me.
Lore MasterWhat plant species are best for producing a lot of calories on a very small space ?
Bananas, nuts, rice.
Grandmaster
Mystagogue
IstariI don't know about Seaweed [or Algae farms] bit for more traditional plants, you don't even need sunlight or that much O2. There are a lot of commercial growers around the world looking Hydroponics with LED lighting at specific frequencies to grow Tomatoes, Salad plants, Strawberries. Flowers and a host of other things faster and "better" and in places they don't currently grow. They use an enclosed environment with increased CO2 and lower O2 levels. The transpiration of the plants is collected, checked for quality/content and recycle it in to the system so there is not much water needed. You need an oxygen mask to tend the crop, if you needed to. Otherwise the place is left alone until the crop is ready.Probably a lot of insects would be used for meat. Low maintenance, little resources needed and lots of protein.
Seaweed and other weeds would be useful as well. They grow quick and as long as you have water, sunlight and and oxygen they should be easy to maintain.
IstariWell, what kind of spaceship are we talking about? What will it be doing and how long will it be in space? What level of technology and money will be going into it? Will there be a habitable centrifuge on board?
Asking how many hydroponic crops it takes to survive is a pretty complicated question. The area of hydroponics is still being explored, so a lot could develop in the future. The smallest number that I found for feeding one person (off of normal soil with expert care directed at the plants) was 0.025 acres, which, if you can maintain your plants at that rate for the long term, leaves you with 1.75 acres of intensely-farmed land.
There's no single plant that you can grow that can meet all of your crew's nutritional needs. Peanuts have a pretty good calorie count, but I don't know that they can provide much nutrients.
Is it practical to breed small animals on a spaceship? Depends on the size of your spaceship. If you're on a tightly-packed personal transport, probably not. If you're on a city-sized asteroid miner, making space for a small pasture probably wouldn't be too difficult.
If I were selecting a farm animal for a small spaceship, I'd probably choose chickens. They can lay eggs very quickly, which I believe provide most if not all of the same nutrients as meat. They have a built-in way of maneuvering in zero gravity (a non-issue if you're raising them on a centrifuge), and they can eat just about anything.
Birds can't swallow in zero gravity, or so I've heard.
I can think of several answers to this, but my first inclination is to ask why this matters. I mean, I assume it does, or you would not ask, but…Can’t you just say there was a large chamber for this and leave it at that?
Mystagogue