LFS gave me pygmy cories and tail-spot pygmies. Will they school?

First of all OH MY GOODNESS these tiny fish are adorable! But I'm a little uncertain about this turn of events.

I went today to get 7 pygmy corys (Corydoras pygmaeus). Got them in the tank and after a couple hours realized 2 of the 7 don't have a stripe but instead have a little black dot. After some Googling I'm pretty certain they are tail-spot pygmy corys (Corydoras pygmaeus).

Now this isn't a problem for me (myself) at all! They're both great. But I know that you're supposed to have a good size group (at least 6 corys is the number I keep seeing) and they need to all be the same species or they won't hang together quite as well so might not feel as safe.

The 7 I have are currently in my 10 gallon by themselves. They stuck pretty close together for the first few hours and still group up at times. But at this point when they group up it's usually just the 5 pygmies and the 2 tail-spotteds are each doing their own thing. I know they are happiest in a group, though, and I want them to have that safety.

My plan has been to try adding in my betta in a few weeks and see how it goes. (I've got a plan ready so I can pull him out at any time if needed.) But now I'm potentially looking at a not-even-the minimum-size school of pygmies and these 2 other guys who will be all alone and possibly more vulnerable.

Do you think they will start schooling together better as they get more used to the tank? Or when the betta shows up?

If you don't think they're all going to become best buds, how should I proceed? I guess theoretically, if the store gets them in, I could have 6 pygmies and 6 tail-spot... But is that overstocked with the betta in a 10 gallon?

Alternately I could return the tail-spots tomorrow and get more pygmies. But I am REALLY liking the tail-spots. I actually think they're a tad cuter than the pygmies. (Shhh... Don't tell them I said that.)

But if the 7 I have now aren't going to form a cohesive group, and 2 separate schools would be overstocking, then it's probably what I need to do.

Thoughts appreciated!

 

I don't suggest getting 2 separate schools, overstocking is not recommended. I'm not sure how the betta will do with the corys either. Best case you just have one type of cory

 

Keep them both! We have 7 pygmies in our 55 gallon. We also have a peppered one, and 7 Panda Cories in that tank, and the pygmies hang with the pandas, and swim the length of the tank with them, and the peppered. They all lay together for daytime naps too. It took them a week to get used to each other, as the Pandas were in that tank first.

I will say that the Pygmies came from a 10 gallon tank, and when I moved them, they got much happier.

 

I don't suggest getting 2 separate schools, overstocking is not recommended. I'm not sure how the betta will do with the corys either. Best case you just have one type of cory

For sure. I do NOT want to come anywhere close to overstocking. I just wasn't sure where that line would be since they're so small. Thanks letting me know 12 total would be too much.

And I don't know how it will go with the betta either, but I'm going to give it a try. It seems to be a really common combo that many have had success with, but other haven't. We shall see!

 

For what it's worth, I have a large-ish (20 or so) shoal of hastatus corys (the two in your pics are hastatus), and they do not all hang together all the time. Even when startled they don't always all shoal up together.

I've always heard that pygmaeus and hastatus were similar enough in size and behavior (mid-water shoalers) to shoal together and be comfortable. Hastatus also are found shoaling with similarly-marked tetras in the wild - the first shoal of them that I bought ended up being partially refunded because the seller discovered (when bagging them up) that two of them were in fact tetras.

 

They will hangout together, but they will not school. They probably will not school, even when the betta comes. I might re-home/return the tail-spot and wait till they have more pygmy corydoras. Good luck!

 

For what it's worth, I have a large-ish (20 or so) shoal of hastatus corys (the two in your pics are hastatus), and they do not all hang together all the time. Even when startled they don't always all shoal up together.

Yes, corydoras hastatus! I had copied and pasted the name from the website that I found to identify them, but obviously the "copy" didn't take and it just pasted the pygmy name again. I tried to fix it in the 1st post but it's not letting me edit that post. Maybe you can't edit after it's so many days old? Who knows.

Interestingly, as I've watched them over the last several days, it seems one of the hastatus seemed to like to stick with 4 of the pygmies. The 2nd hastatus and the 5th pygmy do their own thing. Now, I have no idea if it's consistently the same fish showing these behaviors or if they're all doing some schooling and some separating.

I've been thinking through how to provide more ground cover for them where they can hide out of reach. The sponge filter is attached to the side wall and there's a shadowy space underneath with about 1" of depth that seems to be a favorite resting spot right now.

 

I’d return the spot cories my 10 gal community with a betta is fine

 

they will hang out in same area but not school. I have many emerald cories, 2 false juili, the false chill with them but only swim together.

 

I have 4 different kinds of corys and they all school.

 

You we’re not given what you paid for .

I suggest you simply ask for what you brought.

You have been sold something unfit for purpose.

 

You've given your answer yourself.
When new / uncertain they'll shoal.
When they are more confident they'll shoal less. The hastatus are confident enough to explore on themselves.

Of course one species is better, but if returning and swapping them isn't possible I'd keep them. They are both midlevel swimmers so that isn't a problem.

One thing : think about making them a sandbeach so they can feed on the bottom as well.

 

I wouldn't take them back unless you know the store has more of them; because it's unlikely they'll end up in a better situation.

Hastatus corys are only available for a few months a year, so if the store doesn't have more in stock when you return those two, they won't be getting any more until next September-October. So it's more likely someone will buy just those two and not mix them with pygmaeus.

I agree with DoubleDutch, the reason for keeping corys with others of their kind is first and foremost security, confidence. (Past that would be breeding, and seeing more natural behaviors.) Corys don't stick together constantly when they feel secure, and they don't all exhibit the same level of sociability or need for safety in numbers. It sounds like yours are feeling secure enough, not stressed.

Hastatus in the wild actually shoal with similarly marked tetras, so they're already not set on conspecifics for security. I think pygmaeus are similar enough in size and behavior to be fine for them on the 'security' scale, and certainly better than the chance that the pair might end up going home with someone else who has no other corys.

 

I've been thinking through how to provide more ground cover for them where they can hide out of reach. The sponge filter is attached to the side wall and there's a shadowy space underneath with about 1" of depth that seems to be a favorite resting spot right now.

They really like plants, and it's not uncommon to see them resting on a leaf rather than on the bottom.

I'd probably add an anubias or some java fern; they are rhizome/epiphyte plants that don't need a plant substrate or much by way of care. They're often attached to driftwood, but don't have to be; they'll attach to anything they can grip onto, including plastic decorations. Just weight or tie them where you want them to attach, and within a couple of weeks you can usually remove the weight or string.

My hastatus have several hiding places, but their main go-to (whenever the net or Big Giant Hand appears) is a big clump of java fern that is attached to a decoration, and positioned near a back corner of the tank.

 

They will hangout together, but they will not school.

they will hang out in same area but not school. I have many emerald cories, 2 false juili, the false chill with them but only swim together.

I have 4 different kinds of corys and they all school.

Going to keep saying it because my observations are different. I see the same as Unknown9182.

I now have 7 different kinds in my 250 gallon pool, and all but one of those species do swim together (The 7 current species are paleatus, schwartzi, melini, elegans, trilineatus, brochis splendens, and barbatus; the barbatus don't really shoal with each other, nor with any of the corydoras either. Different genus anyway, they're Scleromystax rather than Corydoras.)

Only one species of those 7 is more likely to be found with its own species than the others, and that is the Schwartzis; but even they still break off into trios, pairs, and individuals. And they will readily join up for a swim or forage with the other species as well, even with plenty of their own around.

These are observations made in a space where they have lots of room to spread out, and lots of company both of their own kind and different species. Where it's more clear what their choices are, less constrained by close tank walls.

Took a video while doing a water change, gave a lower than usual perspective with the floating fishcam. In the video you will see exactly what I'm talking about. Species are slightly different here, this was taken before I got the emeralds and barbatus, and also while there were still a couple of pandas I hadn't managed to catch yet (they're all in their own space now.)

[ DoubleDutch we may also have to add elegans to the 'promiscuous' group too. From around 4:56 to the end you can briefly see an elegans trying to solicit a female paleatus, starting off near the plant basket on the left and then closer to the camera. And I've seen one in the chase group when female paleatus are spawning as well.

Haven't seen a female choose him, there are plenty of male paleatus so they shouldn't have any reason to. Haven't seen him soliciting or chasing the trilineatus females when they're spawning, only the paleatus.]

 

Oriongal makes a good point.

I still say you were not given what you paid for and it is the shops responsibly to fix the situation.

I have a lot of respect for my local club member that posted this video. A look at any of his tanks does make me wonder about this classic “internet story “

 

I have a lot of respect for my local club member that posted this video. A look at any of his tanks does make me wonder about this classic “internet story “

I do definitely recommend that people get six or more of a single species, rather than six mix and match. It's the best choice for many reasons. In the same way I'd probably recommend a 40 Breeder with a sand substrate as an optimal choice for a shoal of regular corys.

Just that it's not the only possible choice, or recommendation.

If a regular cory is sitting at the front of the tank, with a jaunty dorsal fin held high, he's not uncomfortable or insecure no matter how many or few others there are in the tank. If he's confidently foraging all over the tank, he's fine. (I say regular because the pygmies are a bit more nervous than that, even when in a large school. Plus most are also wild-caught.)

Minimum-six of a species is a guideline, and IMO a good one; but I don't think it should be set in stone. My philosophy is generally to let the fish indicate whether they're happy with their situation or not, before applying any arbitrary rules to them. And we can usually tell when they aren't happy.

 

Oriongal makes a good point.

I still say you were not given what you paid for and it is the shops responsibly to fix the situation.

I have a lot of respect for my local club member that posted this video. A look at any of his tanks does make me wonder about this classic “internet story “

It's the evolution/zebra tactic, herds/schools exist for a reason.

1 out of a group that looks same=easier to hide


my false will occasionally 'swim' with the emeralds but disengage after a few seconds - just like when they do it with my tetras. That can be seen as shoaling but it really isn't.

that breeder tank is very full. their proxy & behavior cannot really be determined because it's crowded.

I got the 2 false because I expected to move them into my 20 gallon & buy more. they are 'comfotable' but only hang out in 1/3 of the tank area where as other cory group go everywhere.

 

It's the evolution/zebra tactic, herds/schools exist for a reason.

1 out of a group that looks same=easier to hide


my false will occasionally 'swim' with the emeralds but disengage after a few seconds - just like when they do it with my tetras. That can be seen as shoaling but it really isn't.

that breeder tank is very full. their proxy & behavior cannot really be determined because it's crowded.

I got the 2 false because I expected to move them into my 20 gallon & buy more. they are 'comfotable' but only hang out in 1/3 of the tank area where as other cory group go everywhere.

But in my video several posts above, they aren't crowded.

My definition of shoaling is when one does some action and others join them. I forage, you/we forage. I stop and rest, you/we stop and rest. I set off for a different spot, you/we follow.

I don’t post feeding time because I don't consider everyone eating in the place where the food is to be shoaling. There's no follow-the-leader element there; they're eating because it's feeding time.

The video I posted shows that corys of different species will act with other species the same as they act with their own species, even when there are plenty of their own around. And not only while feeding, and not only in a space where they are forced together by tank size.

They swim together as well. This is a cut of several passes where different species are just swimming. Including some false juliis.

But regardless of that, I still will always recommend six or more of single species before mixing species. My point is not to negate that, at all.

It's to push back against the idea that there is only one answer, and that all corys are exactly the same with the same requirements. In my experience, they aren't all cookie cutouts.

I've been fortunate to be able to have multiple species together in a larger than usual space, and some of my observations were a surprise even to me. I'm sharing them because I know that everyone doesn't have the opportunity to have a similar setup to observe.

Some species seem to be more tight-knit than others, in this space. I have five or six elegans for example, but I never see them together. Paleatus don't seem to care that much about hanging out with each other either; there's probably 20-30 of those, but they are spread out all over the pool and never in one big shoal (unless it's a multi-species one, as in the swimming video.) The schwartzis are more often found in species groups than any of the other species in there, though they do also have their 'independents' that do their own thing.

My aim is not to negate the min-six advice, at all. It's excellent advice. The problem that I'm seeing is that min-six, and 'different corys don't shoal/socialize', seems to be an absolute, set in stone. And I think that is not only not really the case, it can also lead to maybe not-so-great advice.

It's like my recommendation that a 40B with sand is good. If someone then says that they have a 29-gallon, would the advice be to take it back and get a 40B if they're going to keep their corys? Probably not.

I could say (based on what I have), that anything smaller than 250 gallons is not adequate, simply because I see how they spread out, swim, and use that kind of space. Someone with a 600 gallon could say my space isn't adequate, and so on.

But I wouldnt say that anyway, because I recognize that it's also not strictly necessary for them. Nor feasible for most people. They can be perfectly happy in a 20-long, as long as the water parameters are kept up.

The automatic advice to take fish back to the store for this (seemingly) inflexible 'rule' is what concerns me the most, especially when it's about a fish not exhibiting stress.

Because taking them back is stressful. Another round of catching and bagging, another car ride. Another quarantine period in isolation from other corys at the store, if the store takes good care of its stock; because even if you've only had it for a few hours, they can't be sure your tank is healthy. (And the potential for more exposure to disease at the store if they aren't that conscientious.)

Also no guarantee the store has more to put them back with, or that they'll go home with someone who has others or is concerned enough about their welfare to research, come here and ask like the person who is already here did.

IMO, it's much better to leave them where they are if they aren't showing signs of stress, than to insist they must go back and especially only for min-six reasons. That's why I think that the good recommendation shouldn't be turned into an inflexible absolute.