20 Gallon Long: Corydoras & Cardinal Tetras?

[JenTheDroid]

I went to my local pet store, independently owned. I was planning on getting some Corydoras and was planning on 6 but the guy working there told me I only needed 2.   
 

I’m not a big fan on this place because their fish room always looks so bad. Most tanks are never cleaned and obviously they are super expensive. They wanted $8.99 for their albinos. And there never seems to be anyone there to help me. The guy that told me about the Corydoras answered my question and then disappeared and I waited around for like 20 minutes. 
 

Anyway, I have a 20 gallon long. I was planning on getting like 6 Cory’s and like 10-15 Cardinal Tetras. Truthfully, I’d love a bigger schooling fish where I maybe had 5-6 but I haven’t found any. My main focus is the Corydoras. I definitely want them but if I only should get 2 then I feel bad and think maybe I shouldn’t get them. So I was looking for advice or suggestions. 

[T. Payne]

Corydoras definitely appreciate each others company and are schooling fish. For a 2p long you could definitely do a school of 6 to 8.  Cardinals are more of a shoaling fish and you could put a dozen in your 20 long.

[Levi_Aquatics]

The corydoras would definitely do a lot better in a group of 6-8. Maybe you could try some bleeding heart tetras or black skirt tetras if you are looking for a larger schooling fish. 

[Ken]

Your initial plan is spot on. That is way too much for albino Corys.  

[Pizzafan]

Tank looks awesome! Ready to go!

[Guppysnail]

I have kept albinos as a single a pair and a group all thrived To get the most activity and viewing pleasure for you I found a group of minimum 8 to be wildly entertaining but 6 are relatively active as well. Keeping them in larger groups definitely keeps their stress/fear/hiding  level down so possibly extends their life due to not being on high alert all the time. Mine were all given away prior to the end of their life due to working so I don’t know that that statement is true it’s just a guess. 

[jerometnb]

It's a shame that some LF's give terrible advice, especially when the right advice would've made them more money!

[PedroPete]

Maybe consider ordering from AquaHuna? I can't speak to purchasing from them personally but loads of people here can. 

I just got pygmy corys last year, and I have loved them! 

[lefty o]

2 is okay, more is better. looks like you have a relatively new tank, so here's what i would do. get the 2 cory's. give it a few days to a week, then get 2-4 more, wait a few days or a week, then get the tetras.  slowly adding, especially in a new tank will give the bacteria level time to adjust to the new bio-load. just dumping in 20 fish in a fresh tank can overwhelm the beneficial bacteria, and cause ammonia spikes etc.

[Flumpweesel]

It's corys pretty good odds on them increasing their numbers themselves mine did until I added SAEs to the mix. So maybe try three and see if they breed if nothing is interested in their eggs numbers you won't need to do anything. You can always add some later if they don't but it's nice to have room to keep the offspring