Hey all,
One of the aspects of reefkeeping I've always been interested in is the degree to which it can approximate an "ecosystem in a tank." That is to say, I've always been fascinated with hitchhikers - particularly hitchhikers which can form semi-stable breeding populations in our tanks.
Is there any comprehensive list out there of what will basically breed in our tanks on its own, with no particular husbandry on our part?
Off the top of my head:
Cnidarians, Sponges, and Tunicates: The rule with all of these groups seems to be "if you can keep it alive in your tank, and it can reproduce asexually, it will reproduce asexually." Sexual reproduction resulting in viable offspring is just straight-out impossible though.
Crustaceans: All of the common "pods" (copepods, amphiopods, isopods, mysis, etc) breed well in tanks when there is little in the way of predation. In contrast, not a single commonly-kept ornamental is easy to breed, AFAIK, since every shrimp, crab, and hermit has planktonic larvae.
Echinoderms: Since starfish and brittle stars can reproduce asexually through fragmentation, they can form self-supporting populations in our tanks, though typically we only see this happen with Asterina starfish and the very small brittle stars. Sea cucumbers can also reproduce via division, with many having witnessed smaller ones reproducing in our tanks. Sea urchins - and I guess crinoids - are really the only ones left out.
Mollusks: There are of course various hitchhiker snails, like Stomatella and Collonista, which breed well in tanks on their own, along with many pests and semi-pests (vermetids, some nudibranchs, etc). I have heard that some Cerith (particularly the "dwarf" ones),Trochus, and mini-Strombus breed easily as well, though they are more likely to get munched by fish. Most other snails, along with all clams have planktonic young, and thus don't breed in our tanks.
"Worms:" This of course covers multiple groups of life. Generally speaking, common "bristleworms" breed well in our tanks, as do pest flatworms and the tiny spinorbid featherdusters. I know that some of the colonial "cluster duster" varieties reproduce well asexually if your tank can support them. I've had various other worms in my tank - Spionids, spaghetti worms, ribbon worms, peanut worms - but they never seemed to persist in large numbers for long, or were more cryptic, leading me to think that either they don't reproduce as well in captivity, or the fish found them tastier.
Anyway, any other thoughts?
One of the aspects of reefkeeping I've always been interested in is the degree to which it can approximate an "ecosystem in a tank." That is to say, I've always been fascinated with hitchhikers - particularly hitchhikers which can form semi-stable breeding populations in our tanks.
Is there any comprehensive list out there of what will basically breed in our tanks on its own, with no particular husbandry on our part?
Off the top of my head:
Cnidarians, Sponges, and Tunicates: The rule with all of these groups seems to be "if you can keep it alive in your tank, and it can reproduce asexually, it will reproduce asexually." Sexual reproduction resulting in viable offspring is just straight-out impossible though.
Crustaceans: All of the common "pods" (copepods, amphiopods, isopods, mysis, etc) breed well in tanks when there is little in the way of predation. In contrast, not a single commonly-kept ornamental is easy to breed, AFAIK, since every shrimp, crab, and hermit has planktonic larvae.
Echinoderms: Since starfish and brittle stars can reproduce asexually through fragmentation, they can form self-supporting populations in our tanks, though typically we only see this happen with Asterina starfish and the very small brittle stars. Sea cucumbers can also reproduce via division, with many having witnessed smaller ones reproducing in our tanks. Sea urchins - and I guess crinoids - are really the only ones left out.
Mollusks: There are of course various hitchhiker snails, like Stomatella and Collonista, which breed well in tanks on their own, along with many pests and semi-pests (vermetids, some nudibranchs, etc). I have heard that some Cerith (particularly the "dwarf" ones),Trochus, and mini-Strombus breed easily as well, though they are more likely to get munched by fish. Most other snails, along with all clams have planktonic young, and thus don't breed in our tanks.
"Worms:" This of course covers multiple groups of life. Generally speaking, common "bristleworms" breed well in our tanks, as do pest flatworms and the tiny spinorbid featherdusters. I know that some of the colonial "cluster duster" varieties reproduce well asexually if your tank can support them. I've had various other worms in my tank - Spionids, spaghetti worms, ribbon worms, peanut worms - but they never seemed to persist in large numbers for long, or were more cryptic, leading me to think that either they don't reproduce as well in captivity, or the fish found them tastier.
Anyway, any other thoughts?
Last edited:
