Is a "circle of life" type of setup at all feasible?

[lenny]

A thought occurred to me that I think has merit.

If you had a densly planted aquarium with lots of hiding spots, I am thinking you could stock a few guppies and shrimp with the expectation these guys would breed and their fry would be an excellent food source for other fish in the tank. If you maintained stock that wouldn't threaten the breeding parents I don't know why this would work.

Originally I was thinking of setting up a couple feeder tanks for this purpose. That way you would definitely have more control but the idea of creating this little ecosystem I find kind of intriguing.

I know it wouldn't be realistic to expect this to be your main food source, I was thinking just as a suppliment (which is what I'd be doing if I had feeder tanks set up as well).

Can such a setup be sustainable? Thoughts?

 

[aakaakaak]

I think it would be extremely difficult to set this up in a single tank. You'd have to be really careful to establish solid hiding spots the larger fish couldn't get into. You totally wouldn't be able to have it the only food source either.

The breeder tank would probably be your best alternative.

 

[pateceramics]

And what would the fry eat? And the parents of the fry? I don't think you would be able to get enough prey to keep the predators alive if the prey come from the predators as their off-spring. That's why in nature there are 1,000 gazelles for every lion. Think of the smallest pond you've ever seen with a sustained fish population in it. That's how big your tank would need to be. And there would still probably have to be outside in-puts. Ponds have birds that fly in just for the day. Insects that lay their eggs there and then fly away. Predatory mammals and snakes who keep the larger predatory fish species numbers in check.

That said, as an occasional snack... sure, fry get eaten in community tanks all the time!

 

[ryanoh]

Yeah, if you look how much energy loss you get as you go up the food chain, you're looking at lots of tiny, tiny animals like mosquito larva, and maybe just a few fish. This is possible, but I wouldn't think it'd make for that enjoyable of an aquarium.

 

[pateceramics]

And the basis of any food chain is usually plants. You'd need a huge number of herbivorous fish, with an even huge-er number of plants to sustain them, and then a small number of predatory fish. Probably.

 

[lenny]

I didn't expect to be able to set this up as a normal food source, just an occasional tasty treat. I don't care for livebearers because your stock keeps going up. Using these fry as some supplemental food sources though is a good thing. Maintaining a separate aquarium for this purpose only though is a lot of extra work.

I was thinking that if enough shelter was provided that some of these fry could make it for a few weeks before getting eaten and be a worthwhile snack for your fish.

The main food source would definitely have to be commercial food however.

 

[IThinkTherefore]

It would be a great idea for supplemental food, although I definitely agree with you that it is unsustainable as a self-sufficient ecosystem

The best hiding spots that big fish can't get into would be a ton of dense, leafy plants.

A big population of red cherry shrimp could breed and provide fry for carnivores as well. I've also read about people deliberately introducing live blackworms into their gravel, both to work as detrivores/burrowers (like MTS) and as fish snacks