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I've heard mixed opinions about nitrates in aquariums. Some say they're harmful, others claim they help plants. What's the deal with nitrates in a planted tank with Discus?

Nitrates are a byproduct of the nitrogen cycle, and while high levels can stress fish, they're essential for plant growth. In a planted Discus tank, aim for 5-10 ppm. Higher than 20 ppm risks fish health, but below 5 ppm, your plants might struggle. Test weekly, adjust water changes accordingly.

Avila's spot on. I keep my planted Discus tank at 8 ppm nitrates. The key is balance. Too low, and my Amazon Swords start looking sad. Too high, and the Discus get sketchy. I do 30% water changes twice a week to maintain it.

Yo, nitrates ain't all bad. Plants gotta eat too, right? My Discus chill at 10 ppm, and the Valisneria's going nuts. Just don't let it spike, or you're gonna have a bad time.

tideson wrote: ↑Sat Jun 07, 2025 12:15 am Avila's spot on. I keep my planted Discus tank at 8 ppm nitrates. The key is balance. Too low, and my Amazon Swords start looking sad. Too high, and the Discus get sketchy. I do 30% water changes twice a week to maintain it.

Same here. My Discus are way happier since I started keeping nitrates steady. The plants are thriving too.

Nitrates are tricky. In my experience, Discus can handle up to 15 ppm if the tank's well-maintained. But if you're lazy with water changes, keep it lower. My tank's at 12 ppm, and everything's golden.

I've seen nitrates as high as 25 ppm in some setups, but I wouldn't recommend it. Discus are sensitive. Stick to 10 ppm max, and your plants will still get what they need.

It's all about the vibe of your tank. My Discus are cool with 10 ppm, but I've got a ton of floating plants sucking up nitrates. If your tank's bare, you might need to cut it back.

I keep mine at 7 ppm. The Discus seem relaxed, and the Java Ferns are growing slowly but steadily. It's a low-tech tank, so I don't push the limits.

discups wrote: ↑Sat Jun 07, 2025 12:56 am Yo, nitrates ain't all bad. Plants gotta eat too, right? My Discus chill at 10 ppm, and the Valisneria's going nuts. Just don't let it spike, or you're gonna have a bad time.

Exactly. It's about finding that sweet spot. My tank's at 9 ppm, and the Discus are coloring up nicely.