Hello, I'm new here, and need some help...

[Strikh]

Heya.

I have several tanks, and am still relatively new at this hobby (less than a year).

Anyway, I have one 55 gallon tank that is for my live-bearers -- mollies and platys, with a pair of striped cory catfish for house cleaning. A few snails for glass cleaning... I've recently started trying to grow live plants, and they seem to be doing well.

The tank is cycled and fairly well balanced (except for the seriously hard water where I live...) The live bearers have certainly been living up to their name! Lotsa fry from various females.

And this morning, before leaving for work, I saw some "new residents" in my tank, and don't know what they are.

They look like tiny little jelly beans, about an eighth of an inch long. They kinda scuttle along the bottom of the tank, sticking close to the gravel. They appear to have a "front" and a "back", as they "turn around" to change directions.

I've been very lucky so far with births, and I know the cory female was pregnant -- or whatever it's called for egg-layers. She was hiding in her cave this morning, so I couldn't really see if she was any thinner. But they (the corys) are white with black spots and stripes. The "bean-like things" are also white with black spots and stripes. From everything I've read, my chances of breeding corys in a live-bearer tank were supposed to be mighty slim.

Have I gotten very lucky, and had cory fry, or do I have some kind of parasite or something? I did add some new (lily) plant bulbs a few days ago...

I wish I had a camera or some way to show you what they (the new critters) look like, but I do not... :~(

Any ideas?

 

[Christmasfish]

Since your livebearer tank is larger than what people on average have for them, you may indeed have got lucky. Hopefully a member has some baby pictures of their cories.

Though I have found that baby fish of most egg layers types look like tadpoles no matter the eventual body shape. Try using a magnifying glass to get a closer lok at the "beanie" babies. If ya see a wee fin somewhere then you got the brass ring!
Specially since there are no other bottom feeders to threaten the fry.

 

[lmw80]

I believe Guppyman has pictures of guppy fry AND cory fry. Look in his gallery or PM him, as I am sure he will be more than happy to help.

 

[myriam]

Very curious, Strikh.

I have mollies and platies as well, and all my fry have always "looked" like fry--super tiny fish but with obvious heads and tails and fins. I haven't seen that many cory fry, other than Guppyman's pics of them, and those are very obviously "fishy" looking as well.

Jelly beans?! Hmm. I am wondering if these little creatures are not fish types, but some other thing that came along on one of your plants or something.

 

[Strikh]

I do believe I'll be taking one of them -- several appeared overnight -- to the LFS and see what they say. Also going to invest in a magnifying glass and get a better look at them.

 

[Menagerie]

[center:657ebe639d] Strikh, Welcome to AquariumAdvice!! [/center:657ebe639d]
Let us know what they say at the LFS!

 

[RogerMcAllen]

If when you say scuttle you mean they move in pulses, then I know what they are, but not what they are called. I have them all over my tank that I filled with pond water, and in the jar of pond water/algae I keep in my dormroom. Just little pond life, shouldnt' cause any problems at all. I am assuming they came in with a plant.

 

[Strikh]

The only thing I've added recently are some lily bulbs from the LFS. They were pretty dried up, but I was told they'd grow. I rinsed them thoroughly in some water I took from the tank before I put them in. But I suspect that you're right, they came from the bulbs somehow...

 

[marknmelissa]

Strihk,
I think you might have Daphnia magna living in your aquarium (also called water fleas). They are tiny crustaceans that are a great food source for your fish. Look them up on the internet and see if that's what you've got.
-Mark :?

 

[marknmelissa]

They might also be isopods. Check them out.
-Mark

 

[Strikh]

Thanks, Mark!

I do believe you solved the mystery! I won't be able to investigate further until I get home, but it does sound/seem like they are the Daphnia Magna.

LOL, I've fed my fish "freeze dried water fleas", and they love them! I've been looking for more at the lfs', but haven't been able to locate any lately. Could be a case of "problem solved!" I guess they could have come in with the lily bulbs, or they could have somehow grown from the freeze-dried stuff. I did give them a small snack of it last week...

 

[marknmelissa]

They can definitely come in from outside pond material. Good warning to you to be careful to thoroughly wash whatever you put in your tank. These guys are harmless, but who knows what else could come in...

I'll have to check and see if any eggs could survive freeze drying. It's possible for many of the smaller crustaceans.
-Mark

 

[marknmelissa]

Have you identified your little friends?

 

[Strikh]

the lfs had no idea what they were. :~(

They LOOK like Daphnia, but a little different, IMO.

They certainly resemble the pictures I've seen of them on the web, but from what I can tell, they should be kinda clear, with an eye and digestive tract visible through their shell/skin. But my guys are a little more "decorated". They have more swirls and whatnot than just an eye and d-tract. I have mostly live-bearers in that tank (mollies and platys). I've seen them try to eat the little guys, but they end up spitting them back out. Too big to swallow? I don't know. They seem to be peacefully co-existing with all my fish, my snails, and my plants, so I'm not too worried about them.

 

[marknmelissa]

I just remembered. I was just writing a lecture and remembered the name of the guys I think you've got. They are called Ostracods. Check 'em out on goodle images. I won't bother you again about them, but thought you might still be curious.
-Mark

 

[webmoose]

Cory fry when they are really young have a tranparency to them. They are kinda difficult to see at first.. I would never have described any of my cory fry as 'jelly bean like' I would suggest it is something other than cory fry like the others have suggested.

 

[Strikh]

Mark

You're not "bothering" me at all! Thanks for your help! After looking at some images of ostracods, my little guys do look more like some of those pix than daphnia. Looks like there's several thousand species of ostracods, so I'll likely never identify exactly which they are, but that's okay. As long as they're not harmful, they can clean my substrate all they want.