Betta and Harlequin Rasboras

[Juditko]

I've been reading up on compatibility. Our 1 betta is about to upgrade from a 2.5 gal to a 10 gal tank. I would like to add either some harlequin rasboras or cories. I understand on the rasboras it would be five to six for this size tank...if I went with cories instead, which type and how many?

I don't have another tank, so I really need to do my research and see if this is do-able. We are upgrading for easier maintenance, so I will sell the 2.5 gal after the upgrade.

If the safest thing is just to leave our betta alone in the ten, we can do that. I thought it might be nice to have some more action, but I don't want the wrong kind of action!! Please weigh in. I know this is tough because it might all depend on my betta...in which case, if you think that is the end word on the matter, maybe it's wiser to just leave him by himself!

Please weigh in?

[shellieca]

You might want to research Otos instead of Cories, I believe they stay smaller, prefer a minimum group of 3 & are suitable for a 10g. Google the fish you are interested in to see what is required for them as ADULTS & as a tool you can use aqadvisor.com.I have 3 male Bettas in individual 10g tanks & I prefer no other fish with them but to keep them with snails . . . each has 1 Mystery snail & 2 nerite snails.

[Bombalurina]

I would go with a group of six panda cories. They are far less sensitive than otos, although a little less hardy than larger cory species. They are smaller than most cories but larger than pygmies. They are very cute and their bottom-dwelling habits and inoffensive colouring means that they are unlikely to bother or be bothered by your betta. Fast-swimming, colourful rasboras may not be such a good choice. :)
If you go for cories, make sure you have a sand substrate and somewhere dark for them to retreat to, like a cave. :)

[sarahspins]

Pygmy cories (corydoras pygmaeus) could work too.. they stay very small (a little over 1") but don't stay on the bottom as much as most cories, they swim all over. . Salt And Pepper cories (corydoras habrosus) also stay small (about 1-1.5" as adults) if you get the right fish, but I think they are often mislabeled in stores (I'm not sure the ones at petsmart at the right species for example, because I've seen them at about twice the size they should grow to be.. at my LFS the habrosus are teeny tiny, all the other cories are bigger).

Otos are great too but they do much better in schools. I have 15 in my 55 gallon and they swim all over the place and are super active.. I love watching them. Keeping just a handful in my smaller tanks I never saw them move around much and I never did get any to live longer than a couple of weeks before they'd die. I paid more to get my current ones from my LFS instead of petsmart, and they were in much better condition (and some of the ones I got were also tank raised by a customer of my LFS, so I know they didn't get poisoned before they were collected, which is leads to a lot of otos dying within the first few weeks of being purchased).

That said, I have celestial pearl danios in with one of my bettas (and 3 ADF's in with another) in a 10G with no problems - they are small fish and while mature fish do have flashy red fins, they are very fast little fish and like to hide a lot in the plants and I think that helps.

[Fishybitty]

I know my male betta, barely noticed cories. When I had neons in his tank, they stressed him out and he just didn't act like himself.