Originally Posted by 7yl4r
=) This seems post seems to be growing into my own tank biography lol...
I suppose I could ask one of the biology professors here, or maybe I'll just poke around in the physics dept and see if I can find a microscope. =P
I'm really wanting to avoid a complete tear down as I've got several plants growing well, and a few new ones I don't want to disturb, as well as some snails and algae colonies I'd rather not lose.
I wouldn't go so far as to say I'm having problems with fish dying off, as I only had the one, and I think his death was at least in part to do with my (I'm ashamed...) carelessness. I went longer than usual without doing a water change, let the temperature get too low and introduced some new plants without washing them as well as I probably should have.
I think the plan from here is to get just a couple ghost shrimp or small fish (maybe white cloud minnows) and (as bad as I feel about it) see how they fare. I'll also see if I can get my hands on a microscope to try to identify these little specs. =)
Which brings me back around to:
Do ya'll know of any hardy fish that love to eat tiny bugs? =)
If they're the same ones we have, our cory ignored them. Our betta picks at them once in awhile I think. I think they are copepods. Here's a simplified taxonomy key to use if you get your hands on a scope:
(always risky) that they are copepods...
Probably too small for a fish that size to trigger a selective feeding response. In fact after some reading and a couple emails, I'm apt to say that not many, if any, freshwater fish will feed on them selectively after they've passed the fry stage. Probably for the best as some freshwater copepods can be vectors for internal parasites. Numerous small invertebrates will prey on them, but most will metamorphose into flying insects.
If you like weird critters (and I get a sense that you might), you might try and find some hydra - they eat copepods, zooplankton and just about anything else they can get their tentacles on including small fish. The 'sea cucumber' type thing you found might have even been one. Would limit (or eliminate altogether) your fish choices, but you'd probably be the only guy on the block with a dedicated species tank for hydra. Would definitely take some creativity to flesh out the details, but I actually think this would be a very cool idea for a small tank.
Could not locate any definitive information, but can almost guarantee anything that sifts microfauna from the substrate will also eat them. Crayfish - almost guaranteed. Ghost shrimp - probably. Crabs - probably.
End note - the population of copepods in a freshwater tank will probably not support any of the above without additional feeding.