Category Overview • Intermediate Fish

Not all aquarium fish are ideal for absolute beginners — but they’re also far from “expert only.”
Intermediate-level fish are perfect for aquarists who have mastered the basics and are ready for something slightly more challenging and rewarding.

These species often show richer colors, more interesting behavior, or greater personality, but they may require more stable water, better tank mates, or more specific feeding routines.

What Makes a Fish “Intermediate”?

Needs more consistent water parameters
Benefits from a fully established, stable aquarium
May show aggression or stress in the wrong setup
Often requires specific diet (live or frozen)
Needs careful tank mate selection
Hardier than advanced fish, but not effortless

The Best Intermediate Freshwater Fish

1. Dwarf Gourami

Vibrant, peaceful, but sensitive to water quality.
Best in stable, well-maintained tanks.

2. Pearl Gourami

Beautiful schooling fish that thrive in calm, clean aquariums.

3. Mollies (Especially Sailfins)

More demanding than guppies/platies.
Prefer harder, mineral-rich water.

4. Cherry Barbs

Hardy but active. Do best in stable, planted tanks in proper groups.

5. Angelfish

Not difficult long-term, but require good tank size and stable warm water.

6. Bolivian Rams

Peaceful cichlids that thrive in stable, clean tanks with soft water.

7. Black Skirt / Serpae Tetras

A bit more sensitive and nippy than beginner tetras.

Who Should Choose These Fish?

Pick intermediate fish if you:

Can maintain a cycled tank consistently
Understand community compatibility
Are comfortable feeding more varied foods
Want fish with richer behavior and personality

They reward good care and are a natural step up from beginner-friendly species.

Related Guides

🏁 Final Thoughts

Intermediate fish offer an exciting next step in the aquarium hobby. With just a bit more attention to water quality, diet, and tank mates, these species thrive — and give you a more dynamic, beautiful tank in return.