Hi, I was wondering if anyone could help me identify some eggs I found in my tank.

The first batch I noticed is on one of the the acrylic walls in my tank and numbers six. They're all about 1 milimeter wide and are surrounded by jelly. I first saw them the day I put in a red ramshorn snail, and that coupled with the jelly led me to think they're snail eggs. That was all fine and dandy and I would have thought nothing more of it had I not found a second clump of eggs on one of my plants, individually perhaps half the size of the supposed red ramshorn eggs but in greater quantity (between a dozen and two dozen). They might be covered in jelly too, but I'm not sure.

Right now my suspects are the ramshorn and my two oto's, who are the only critters in the tank large enough to lay these things. My question is, which one belongs to which? I've read that oto's only lay a handful of eggs so perhaps the six-pack is theirs, but then again the six-pack sort of looks like an enlarged version of what the pond snails lay. Plus it definitely has that jelly covering, and I have no idea if that's snail-specific or not. Then again a 'handful' isn't too specific, so in fish-terms that might mean 'less than 50' instead of 'four or five'.

From the information I've gathered so far, neither really seem like otocinclus eggs, but that's precious little info and I haven't managed to find any pictures of oto or ramshorn eggs to confirm anything. Any help in ID'ing them would be much appreciated, thanks.


P.S. Excellent site, Robyn! Lots of great info, I have a bunch of limpets and was going crazy trying to figure out what they were, your site was one of the few that had that info.

If you're positive that the two batches of eggs are different in size, then I would say the ones are the glass are snail and the others ottos. You say the other animals couldn't have done it but you should list all the animals because maybe one of them did lay the eggs. What else is in the tank? Do you have any other species of snails or catfish? Ottos normally would lay on plants but don't breed to often in captivity. Snails breed a ton of course and will lay on both glass and plants. I've never seen otto eggs or photos of them but would expect only about a dozen tiny eggs from one spawning. Fish eggs have some jelly but only around each individual egg whereas snail eggs have the jelly over an entire clutch of eggs. If you can see the ones on the plants better, that might help tell if they are fish or snail.

Ah, thanks! Yesterday I clipped off the leaf the smaller eggs were on and stuck it in a makeshift net breeder made from one of my larger fish nets (unfortunately I think the net would still let small fry pass through, I'll have to buy a real one today or cover up my filter intake) and managed to get a closer look at them. I counted approximately 16, no more than a millimeter wide and probably less, and there appears to be some kind of thin film covering them (I could be imagining it, at any rate it's not nearly as pronounced as the jelly covering snail eggs and might be individual egg jelly blending together or something). They're mostly transparent, but in good light the central area of each egg has a light amber sheen.

The only other creatures in my tank are limpets (who seem far to small to lay such a large clutch) and various other smallish animals like planaria, those teeny oval shaped swimming things (protozoan maybe? I always thought those were microscopic) . . . anyway, just your typical plant hitchhikers. No pond snails, just the one ramshorn. No fishies other than the otos.

I too really doubt my otos have bred, as it seems far too lucky with just one female and one male, in a fairly new tank. I wasn't even too sure they'd survive for long, having read the reports of oto die-offs soon after being introduced to a new home. Maybe them being the only fish in the tank helped (it's basically just an underwater garden). Anyway I guess from now on I'll just assume they're oto eggs and treat them as such, although I think the chances are that they're from some unknown thing in the tank. My female oto's belly is and has been pretty small, even moreso than the male's, and I've read gravid females are supposed to be really fat.

Thanks again for the help!

P.S. Do you think it's okay for the eggs to be exposed to a lot of light? My makeshift fry net is at the top of the tank, about two inches away from two 15 watt flourescents, with the clipped leaf floating egg-side-down inside of it. The lights and the water column are separated by a thick acrylic window so I'm not so much worried about heat as I am worried about the light giving them sunburn or something *shrug*

Normally, the intensity of artifical fluorescent light is immensely less than natural sunlight. I wouldn't worry too much about it. If the eggs are to be right under the light, put in a few floating plants to block some light and give more cover.

Thanks again. It's amazing how you take the time to respond to every single post, I don't know of any forum that gets half as much attention from it's creator as this one, now we know how your ponds feel :lol: