Who Gives A Fish Forums

I've got a 55 gallon tank with 10 Neon Tetras, 6 Corydoras, and a pair of Angelfish. The tank's been running for about 6 months, but I'm worried I might be pushing the stocking limits. How do you guys gauge when enough is enough?

Honestly, it's all about the vibe of the tank. If your fish are chill and not showing stress, you're probably good. But if you start seeing aggression or weird behavior, that's a red flag. Also, keep an eye on your water params, especially nitrates. If they're creeping up too fast, you might need to cut back.

A 55 gallon is decent for what you've got, but Angelfish can get territorial as they grow. I'd recommend checking your filtration capacity too. A canister filter rated for 100 gallons would give you more wiggle room. Also, how often are you doing water changes?

Stocking levels aren't just about fish count. It's about bioload and compatibility. Angelfish might snack on Neon Tetras when they're bigger. You might wanna consider rehoming the Tetras or upgrading to a 75 gallon if you're attached to the Angels.

Thanks for the input. I do weekly 25% water changes, and nitrates stay under 20 ppm. The Angels are still juveniles, so I'll keep an eye on their behavior. Maybe I'll hold off on adding anything else for now.

folden wrote: ↑Fri Jun 27, 2025 12:11 am Thanks for the input. I do weekly 25% water changes, and nitrates stay under 20 ppm. The Angels are still juveniles, so I'll keep an eye on their behavior. Maybe I'll hold off on adding anything else for now.

Sounds like a solid plan. Your water change routine is on point, so that's a good sign. Just watch those Angels as they grow.

If you're curious about exact numbers, the inch-per-gallon rule is a rough guide, but it's not perfect. Your tank's dimensions matter too. Tall tanks like yours give Angels more vertical space, which helps. What's your substrate like? Sand or gravel?

The inch-per-gallon rule is sketchy at best. It doesn't account for fish activity or waste production. Corydoras, for example, are low bioload but need floor space. Your tank's footprint is more important than volume for them.

coralux wrote: ↑Fri Jun 27, 2025 2:21 am The inch-per-gallon rule is sketchy at best. It doesn't account for fish activity or waste production. Corydoras, for example, are low bioload but need floor space. Your tank's footprint is more important than volume for them.

Yep, totally agree. That's why I never rely on it. Gotta think about how the fish actually use the space.

Another thing to consider is plant density. If you've got a lot of live plants, they can help with nitrates and give fish more hiding spots. What's your lighting situation? Low-tech or high-tech?