Stocking plan for 180L tank

[fluke]

And don't forget to dim the lights when you first add them. Bright lights can freak 'em out after being in a dark bag.

[wave_crest]

Take your time with acclimation. Float the bag for 20 minutes, then slowly add small amounts of tank water every 10 minutes for an hour. It reduces stress and helps them adjust.

Exactly. Also, test your water params beforehand. Cardinals are sensitive to nitrates, so keep them below 20ppm.

[riverrush]

If you're adding Corydoras, make sure your substrate is smooth. They love to sift through sand, and rough gravel can damage their barbels.

[rizen9]

I use pool filter sand in my tank. It's cheap, looks natural, and the Corydoras love it. Just rinse it well before adding to the tank.

[200GalMan]

Also, consider adding some driftwood and plants. They provide hiding spots and make the fish feel more secure. Java Fern and Anubias are easy to grow and don't need much light.