So fun DIY projects but as a serious way to grow food it’s terrible, not economical or sustainable

By this logic, doing anything yourself is inefficient and a waste of time. However, I think that by reducing it purely to a monetary number, you are not measuring things correctly. Part of the output of doing DIY things is the knowledge, experience, and fun that comes from doing it. If you insist on putting a dollar sign on that, I’m sure it ends up being much more equal.

Yep. I initially looked into it as a potential avenue for sustainably producing some of my own food, but the math absolutely did not make sense. Growing a bunch of potatoes in a barrel would be a lot more bang for your buck with that goal in mind. To really optimize costs and labor, though, as you say, you need a greenhouse and/or a big old field, just like always. There are no small-scale shortcuts. Not yet, anyway. It makes me a bit sad that even with modern tech we haven't really made it much easier for people to produce their own food. But it's a reminder that our food production requires large scale collaboration and cooperation. Maybe that's a good thing.

So... This is more comparable to a guppy tank than a farm. Generally, yes you are right. Home farming (eg vegetable gardening) generally isn't economical. That doesn't mean it's not valuable. Besides being fun... I do think home gardening some resilience to the food system. Aquaponics is, in general, not really a viable commercial method. Or rather, the plants are just a filter for the pinds...not a true secondary product. Still... aquaponics is fun.

Nobody is arguing this will replace farming, nobody disagrees with you. The point is that it's fun and you learn something.

Who cares? When you buy a couch, are you thinking "will this couch offset the value of the square footage it occupies" or "will this couch be comfortable and match my décor?" I'm glad someone is doing something fun in their home.

People seem to think you’re attacking the article. I read the article but know nothing about aquaponics otherwise, and I was wondering why we don’t see it used more. So I appreciate you sharing your knowledge on the subject.

It's less about the square foot economics for at-home, and quite often the time to travel between growing space and home, if in the case of an apartment, it was somewhere else.