preditor prey relation in the home aquarium

this winter i added snails too two tanks of mine.
the smaller tank has way less algae for the snails to eat and no predatory specie in tank and there not laying eggs.
the snails in the second tank has daters in with them and plenty of algae to eat the more they eat the more egg-laying they do.
all of my fish are over fed im sure because i will let them eat until they just stop feeding
my darters eat blood-worms daily and feed on the pond and ramshorn snails @ night
on the mornings i see lots of empty shells i will also have darters missing from the tank.
the larger preditors in the tank must get into a hunting mode as the smaller fish prey @ night
and it cant be from hunger.last night must have been one heck of a hunting party
all pond snails are gone and 4 ramshorn shells a empty,plus two daters over 3" are missing.

this winter i added snails too two tanks of mine.
the smaller tank has way less algae for the snails to eat and no predatory specie in tank and there not laying eggs.
the snails in the second tank has daters in with them and plenty of algae to eat the more they eat the more egg-laying they do.
all of my fish are over fed im sure because i will let them eat until they just stop feeding
my darters eat blood-worms daily and feed on the pond and ramshorn snails @ night
on the mornings i see lots of empty shells i will also have darters missing from the tank.
the larger preditors in the tank must get into a hunting mode as the smaller fish prey @ night
and it cant be from hunger.last night must have been one heck of a hunting party
all pond snails are gone and 4 ramshorn shells a empty,plus two daters over 3" are missing.

WoW... I couldnt stand those kinds of losses of my little Darter buddies . You didnt say what else you have in that tank, whats eating your darters ?? . The snails are nice and i wouldnt miss a few of those but losing Darters......

WoW... I couldnt stand those kinds of losses of my little Darter buddies . You didnt say what else you have in that tank, whats eating your darters ?? . The snails are nice and i wouldnt miss a few of those but losing Darters......

the pickerel is new so i would say thats the one. this fish needs allot of live food 6 minnows every other day or so and it still hunts down other fish
i think he will be moved to the other 55 gallon tank next week.

definitely the Pickerel. They will eat til they can't move if you let them

A lesson I learned the hard way - if a fish will fit in another fish's mouth, it will probably end up there. Doesn't matter how much you feed them, they seem to prefer fresh meat.

Things change when you confine fish in a smaller area. Darters and bluegill can coexist in the wild, because they have more room to move around and hide. In a tank, there's less room to run. Even large darters will eat small ones, and let's not get into how large a fish can fit into a banded sculpin's mouth. Larger than you might think.

A lesson I learned the hard way - if a fish will fit in another fish's mouth, it will probably end up there. Doesn't matter how much you feed them, they seem to prefer fresh meat.

Things change when you confine fish in a smaller area. Darters and bluegill can coexist in the wild, because they have more room to move around and hide. In a tank, there's less room to run. Even large darters will eat small ones, and let's not get into how large a fish can fit into a banded sculpin's mouth. Larger than you might think.

This fish is a eating machine and hunts for fun and it will be his undoing for sure

This fish is a eating machine and hunts for fun and it will be his undoing for sure

Awww, Tony dont be so harsh on the little guy he is doing exactly what he was made for...lurking around and ridding fish tanks of tasty unnecessary extra fish, lol. one of gods little ways of keeping everything under control.

Awww, Tony dont be so harsh on the little guy he is doing exactly what he was made for...lurking around and ridding fish tanks of tasty unnecessary extra fish, lol. one of gods little ways of keeping everything under control.

TRUE, but some were to stay.

TRUE, but some were to stay.

Thats how it begins. Now that the pickerel is captive, you can't release it. So that justifies setting up another tank. Vicious cycle.

This is something I've wondered about, not just with native fish but with any type. Has anyone ever set up a self sustaining tank in terms of predator vs prey? Meaning, having the prey species replace losses fast enough to to keep their population steady. I figure with the livebearers they reproduce fast enough to handle a small number of predators. And with Hets and their birth spacing, if you have around 50 Hets in an aquarium, would that be enough to keep a few madtoms and darters fed?

...And with Hets and their birth spacing, if you have around 50 Hets in an aquarium, would that be enough to keep a few madtoms and darters fed?

That's a good question. Anyone ever tried something like this?

Brian

I have, once upon a time in a far away place. You need to be very disciplined about minimizing the number of predators though. I doubt 50 Heterandria would provide food for "several" madtoms AND darters. I'm sure you could do one though. My own experiment had just a pair of fish, a sculpin and a stickleback, with mussels and live plants for filtration. The fish did well on the self-reproducing invertebrate population for quite a while. It makes for a pretty sparce tank though unless you really like to watch daphnia.

Guppies or gambusia would work better, Heterandria probably aren't prolific enough.

I did an experiment with a 10 gallon with some ferocious water bugs(Abedus sp.) and guppies. Indeed they didn't get enough of the guppies that had I started with both sexes of guppies(only female, and they ate most of their fry) I bet this could have been kept going without the guppies running out. However, as a precaution the ferocious water bugs were fed quite well.

I haven't had good luck breeding Gambusia in an aquarium. They seem to very much enjoy eating their own young unless the tank is ridiculously thick with floating plants, and even then they don't survive long.