How many cardinals should I add?

[7toes]

Hi everyone. I have a moderately planted 20H with 2 honey gourami, 6 cherry shrimp, 6 habrosus corydora, and 4 neon tetra. Originally I had 11 neons but unfortunately I got a bad batch.

A local fish keeper near me has a good deal for 10 cardinal tetras. Would 10 be okay to add? I have 2 sponge filters both rated 20gal (totaling 40gal).

Originally I was going to add just 6 cardinals but I’m tempted on a bigger school. I’m mostly worried about crowding the tank.

 

[Sgooosh]

get the 10 but split it up into different tanks since that might be too much for a 20

 

[Colin_T]

don't get cardinals, just get 10 more neons

 

[itiwhetu]

What is the pH of your tank

 

[Carp890]

Hi everyone. I have a moderately planted 20H with 2 honey gourami, 6 cherry shrimp, 6 habrosus corydora, and 4 neon tetra. Originally I had 11 neons but unfortunately I got a bad batch.

A local fish keeper near me has a good deal for 10 cardinal tetras. Would 10 be okay to add? I have 2 sponge filters both rated 20gal (totaling 40gal).

Originally I was going to add just 6 cardinals but I’m tempted on a bigger school. I’m mostly worried about crowding the tank.

I think that's fine cardinals very friendly fish 10 would be fine good luck pal

 

[7toes]

What is the pH of your tank

pH is 7

 

[itiwhetu]

pH is 7

Neons will be better in this tank than Cardinals with a pH of 7

 

[7toes]

Neons will be better in this tank than Cardinals with a pH of 7

The neons I got from my LFS were absolutely awful. I really don't want to order mass-produced neons again because of the quality; as I said I got 11 and almost all of them died... If I get more, I have a feeling the same thing will happen. How do I get neons that are better quality? Or can I go for a different variation of neons like green or black?

 

[itiwhetu]

The neons I got from my LFS were absolutely awful. I really don't want to order mass-produced neons again because of the quality; as I said I got 11 and almost all of them died... If I get more, I have a feeling the same thing will happen. How do I get neons that are better quality? Or can I go for a different variation of neons like green or black?

Neons in general aren't that great in this day and age. I have always liked Black Neons they seem to be strong and hardy. I am a big fan of Black Phantom Tetras and always have been

 

[Byron]

The neons I got from my LFS were absolutely awful. I really don't want to order mass-produced neons again because of the quality; as I said I got 11 and almost all of them died... If I get more, I have a feeling the same thing will happen. How do I get neons that are better quality? Or can I go for a different variation of neons like green or black?

A couple things to recognize here.

Green neon tetra, neon tetra, cardinal tetra and black neon tetra are four different distinct species, and to the fish, that matters a lot. Each species of characin (tetras are all in this family) lives in large groups, and without going into the details, there is clear scientific evidence that a group of 10 or more of a species will always fare better. So you are better staying with one species, since there is certainly not space here for a group of 30 or 40. Cardinal and green neon tetras are closer related than either is to the neon. It would be better not to combine neon tetras and cardinal tetras.

If you can find a supplier of wild caught fish, you would probably have better luck, provided you have soft water. The GH is much more important to soft water fish than the pH.

Adding to the Corydoras habrosus group would be advisable too; another 4 or 5 added to the existing six would improve the welfare of this fish. I will assume you have a sand substrate which cories need in order to be t their best.