Who Gives A Fish Forums

Looking for some medium-sized fish ideas for my 40-gallon tank. It's planted with Anubias and Java Fern, and I've got a sand substrate. Water params are good, 0 ammonia, 0 nitrite, 10 nitrate. What's worked for you guys?

I'd go with a school of Congo Tetras. They're chill, colorful, and won't mess with your plants. Mine are in a 55-gallon with similar setup, and they've been thriving for over a year. Just make sure you've got a decent filter, they like some flow.

northo wrote: ↑Sun Aug 31, 2025 10:23 pm I'd go with a school of Congo Tetras. They're chill, colorful, and won't mess with your plants. Mine are in a 55-gallon with similar setup, and they've been thriving for over a year. Just make sure you've got a decent filter, they like some flow.

Second this. Congo Tetras are solid. If you want something a bit different, Rainbowfish are another great option. They're active and hardy, plus they'll add a lot of movement to your tank.

I've got a pair of German Blue Rams in my 40-gallon. They're smaller but pack a lot of personality. Just keep the water warm, around 82°F, and they'll do great. They're not plant destroyers either, which is a plus.

Thanks for the suggestions, everyone. I'll look into Congo Tetras and Rainbowfish. Rams sound cool too, but I'm not sure about the higher temp requirement.

If you're iffy on the temp, maybe check out Pearl Gouramis. They're peaceful, medium-sized, and don't need crazy warm water. Plus, they've got that cool lace-like finnage. Just avoid keeping them with super aggressive tankmates.

Pearl Gouramis are a good call. Another thought: Bolivian Rams. They're like German Blues but more tolerant of lower temps, around 76-80°F. They're also less picky about water params, which is nice if you're still dialing things in.

hush wrote: ↑Mon Sep 01, 2025 12:13 pm Pearl Gouramis are a good call. Another thought: Bolivian Rams. They're like German Blues but more tolerant of lower temps, around 76-80°F. They're also less picky about water params, which is nice if you're still dialing things in.

Yeah, Bolivian Rams are underrated. They've got that same cool look without the fuss. Just make sure you've got some hiding spots, they like to explore.

If you're into oddballs, consider a group of African Butterfly Fish. They're surface dwellers and add a weird vibe to the tank. Just don't keep them with anything that'll nip their long fins.

African Butterfly Fish are neat, but they're kinda specialized. If you're going that route, make sure you've got a tight lid. They're jumpers. For something more mainstream, maybe a school of Denison Barbs? They're active and striking, but they do need some swimming space.