Will salt & pepper and peppered Corys school together?

[Ianvaldius]

Let's sort this out for you. Corydoras are shoaling fish, and they are highly social (not all shoalers are, it varies). Programmed into their DNA is the expectation that they will be in large shoals/grooups, and when this is denied them they can be stressed and that leads to other problems. With a few exceptions, each species of Corydoras in their habitat live alone or maybe two species, in numbers up to the hundreds.

In an aquarium, numbers are important for the health of the fish. Numbers more than species seems to be the case. I have some 41 cories representing 12 species in my "cory" tank. Spawning is regular, some fry even manage to survive (actually, it is the egg surviving and hatching). I always try to acquire at least five of a species, but sometimes for various reasons this is not possible. But it is the number in total that is the important factor to the health and well-being of these fish.

Having said that, I have observed that my pandas do seem to be more "together" than some of the other species, but this may just be my impression from the fact that this species is considerably more active in an aquarium. They like to "play" in the filter stream much more (some species never do this) so they are together much more.

As for the "salt and pepper" cory, if this is Corydoras habrosus, I would not acquire these. This is one of the "dwarf" species, and they tend to do better in larger groups of their own. I don't know what other fish are in this tank (aside from the existing cories).

The other thing to keep in mind about cories is that they should not be combined with any other substrate shoaling fish, thinking here of loaches. Have more cories, fine. You can have some of the loricariids (small plecos, whitptails, etc) but not loaches.

In a tank as large as the one mentioned here, you should have at least 15 Corydoras, and you could go up from there if you like, but no fewer. If the 75g is the tank, I would have at least 40-50. It will make a considerable difference to their health and "happiness." And I'm sure we all as aquarists want to provide a good environment; the fish will in most cases live the rest of their lives in whatever situation we provide for them.

Thank you for all of the info! I have a number of mid to upper level fish in my tank, in addition to some ADFs, clown loaches, and a rainbow shark in with the cories. So far I haven't seen any detrimental behavior between any of these species. The Kuhli loaches are in a 20 gallon of their own with some black neons and guppies. What are the downsides to keeping them with loaches or other substrate shoaling fish? Should the loaches be moved to my 75g (currently in the process of being set up) and which species would do better (clowns or corys) with my kuhlis?

 

[Byron]

Thank you for all of the info! I have a number of mid to upper level fish in my tank, in addition to some ADFs, clown loaches, and a rainbow shark in with the cories. So far I haven't seen any detrimental behavior between any of these species. The Kuhli loaches are in a 20 gallon of their own with some black neons and guppies. What are the downsides to keeping them with loaches or other substrate shoaling fish? Should the loaches be moved to my 75g (currently in the process of being set up) and which species would do better (clowns or corys) with my kuhlis?

To be honest, you have some serious issues here with the combinations/numbers. First, loaches should never be housed with cories. Second, clown loaches are huge, they need at minimum an 8-foot tank, and a group of five (or more). They should never be housed with kuhlii loaches. Third, rainbow sharks should not be housed with cories; they can work sometimes with certain loaches (not kuhlii).

To the issue of not providing the above...you may not see detrimental behaviour, but that does not mean there is not a problem. Each species of fish has evolved over thousands of years and it has inherent behaviours and requirements programmed into its DNA. None of us is going to change this, so we should research the species to understand what it needs to be in good health and then provide that. The "silent" problems between these fish cannot be seen; pheromones and allomones are chemical signals of communication among fish and we cannot see or read them. We just know they are there, affecting the fish. The adverse conditions can cause fish to behave contrary to the norm, but this is also causing serious stress, and that only makes things worse as it progresses.

 

[Ianvaldius]

To be honest, you have some serious issues here with the combinations/numbers. First, loaches should never be housed with cories. Second, clown loaches are huge, they need at minimum an 8-foot tank, and a group of five (or more). They should never be housed with kuhlii loaches. Third, rainbow sharks should not be housed with cories; they can work sometimes with certain loaches (not kuhlii).

To the issue of not providing the above...you may not see detrimental behaviour, but that does not mean there is not a problem. Each species of fish has evolved over thousands of years and it has inherent behaviours and requirements programmed into its DNA. None of us is going to change this, so we should research the species to understand what it needs to be in good health and then provide that. The "silent" problems between these fish cannot be seen; pheromones and allomones are chemical signals of communication among fish and we cannot see or read them. We just know they are there, affecting the fish. The adverse conditions can cause fish to behave contrary to the norm, but this is also causing serious stress, and that only makes things worse as it progresses.

Thanks. So between the three tanks, would it be a good idea to house the rainbow and the clowns in the 75, leave the kuhlis where they are, and leave the corys/add more corys to the 55? Naturally, I want the fish I have to lead healthy lives. I didn't research the fish I have extensively when I first got them and experienced a number of deaths, so I've been trying to do a lot of research over the past couple weeks (the reason I bought the 75 gallon) because I don't see my girlfriend wanting to part with the fish we currently have- only improve their living situation. It's been like pulling teeth to get her to cede that we should probably get more corys and clowns, but it's progress.

 

[Byron]

Thanks. So between the three tanks, would it be a good idea to house the rainbow and the clowns in the 75, leave the kuhlis where they are, and leave the corys/add more corys to the 55? Naturally, I want the fish I have to lead healthy lives. I didn't research the fish I have extensively when I first got them and experienced a number of deaths, so I've been trying to do a lot of research over the past couple weeks (the reason I bought the 75 gallon) because I don't see my girlfriend wanting to part with the fish we currently have- only improve their living situation. It's been like pulling teeth to get her to cede that we should probably get more corys and clowns, but it's progress.

Yes to the tank housing suggestions. The rainbow shark Epalzeorhynchos frenatum is, according to the info on Seriously Fish, compatible with Chromobotia macracanthus (clown loach), though one has to realize nothing is guaranteed.

The clowns do need an 8-foot tank and a group of five, and soon, or they will have serious problems. Tell you girlfriend that you do not want to continue the cruelty to these fish, and there are two options, a huge tank now, or re-home them.