[Michael Hoaster]

That's funny, you can tell you and I come from two different 'camps'. You have a more 'nano tank' point of view, and I'm from the 'bigger the better' side. I would have said,"the larger the tank, MORE possible it is to create a self-sustaining ecosystem." For example, I could probably fill my 240 with enough micro and macro algae to support one herbivorous fish. So I could build a self-sustaining tank, but it would not be very interesting as a display. But I couldn't do that with a small tank. It couldn't grow enough algae to support a herbivorous fish. It would consume quicker than algae could regrow.

I'd like to hear more about a reef in a jar. How does smaller make it MORE possible?

As for my fish (consumers) list:

Chromis, Royal Gramma, Chalk Bass, Swiss Guard Basslet, Neon Goby, Silversides - Planktivores
Blennie, Cherub Angel, Blue Tang, Molly, Snails - Herbivores/Detrivores
Lookdown - Carnivore (small fish & crustaceans)
Shrimps and crabs - Omnivores
Rock Beauty - spongovore, detrivore, herbivore
Sponges, Sea squirt, Scallop, gorgonia, anemone, zooplankton - planktivores, bacteriovores

Producers:
Manatee Grass, Chaeto, Ulva, various red Macro Algae, microalgae, Phytoplankton, diatoms, cyanobacteria

Clearly, I've got more planktivores than my tank could sustainably feed, even with a refugium. So either I drastically reduce their numbers or I feed them. Some of my herbivores can sustain themselves with what's produced in the tank. But the larger ones like the Blue Tang will likely need feeding. I'll need to feed the Lookdowns as well, if I don't want them to eat any of the smaller fish. The tricky part will be closing the circle with all the bacteria and detrivores, that recycle fish waste, uneaten food, etc. to feed the plants. But the size of my tank will limit what can be recycled, so I'll have to export excess pollutants with water changes, macro algae pruning and removal of excess seagrass.

So, I don't expect my tank to be completely self-sustaining, but I will aim to get as close to it as is reasonably possible. And this will make it easier on me to maintain it.