In the process of reading the PETA thread, 2 thoughts occured to me:
Some people keep personal aquariums in which they raise fish.
Some people eat fish.
Logically combining these would yield
It should be possible to build a personal aquarium in which to raise fish for eating.
AFAIK, I’ve never heard of anyone doing this and I assume the main reason is that it’s simply not cost effective. But say I did want a personal fish farm, how would I go about it? What are the minimum specifications for the tank? What species would work well? How much money/time are we looking at? What are some problems that may occur?
It’s been a long time since I looked at aquaculture, but carp and tilapia are two species that are raised in ponds and are pretty robust. They would probably handle being raised in a large aquarium. You frequently see carp and other fish kept in aquariums in Asian restaurants like you see live lobster, but this is storage more than aquaculture.
As a wild guess, I’d think of something like the State of NH uses for raising stock fish.
Basically, it’s a long rectangular concrete box, which water flows through (I think they capture streams, or springs, in a few cases). Block off the inflow and outflow locations, so that your fish don’t escape. Feed. Harvest when big.
As to what species, they grow trout and salmon. What works in your area would depend on your climate.
This, though regional for Virginia, in the USA might give you some information.
If you want to use a household aquarium, the bigger the better. Less than 50 gallons probably wouldn’t be worth the effort. I’d go with talapia or catfish as trout and salmon require cold water which is problematic inside a house. If you got the fish as fingerlings, you could expect to be rasing them for at least a year or two for them to reach pan size. I suspect that after keeping them for a couple of years they would become pets and not food.
I read an online article somewhere about raising catfish in a large plastic water tank (the kind used as a header tank in homes with sporadic water pressure); the kitchen scraps went into a wormery compost bin, the worms were fed to the fish and the people ate the fish. Catfish are apparently good for this because they will tolerate more challenging water conditions that a lot of other kinds of fish, and also because they aren’t fussy about what they eat. I’ve never eaten catfish, much less one raised entirely on compost worms, so I can’t comment on the overall efficacy of the idea.
No, it wouldn’t be cost effective in a home aquarium. You need the water quality to be very good, much better than the water quality in a typical home aquarium, where, despite how clean the water looks, there’s still a much higher concentration of bacteria, toxins, etc. Fish in ponds & streams can have 1000’s of gallons of fresh water flowing past them each hour.
In a home aquarium, you’d need to simulate that the best you could with expensive filters and regular water changes. By regular, I mean almost daily changes of 1/3 - 1/2 the volume of your tank. You’d probably want your tank to be at least 100 gallons.
It would take a lot of electricity & water to run this. Back in the day, when I was big into freshwater tanks, with all the equipment I had running, my monthly electric bill went up about $40/month. That’s not counting the cost of replacing filter materials, light bulbs, etc.
I started a similar thread once, that got some good info. I’d still like to do it one day.