Who Gives A Fish Forums

I've heard mixed things about nitrates and Discus. My tank sits around 20 ppm, but I'm worried it's too high. Anyone run theirs higher without issues? I do 50% water changes weekly, use a Fluval 407, and keep them at 84°F with sand substrate.

20 ppm is manageable if it's stable. Wild-caught Discus are more sensitive, but domestics can tolerate up to 40 ppm if acclimated slowly. Key is consistency—no spikes. What's your feeding routine? Overfeeding can crank nitrates fast. I run mine at 30 ppm with daily 10% changes, Eheim 600, and they're breeding fine.

Yo, my crew chills at 50 ppm, no probs. But they're tank-raised beefheart junkies. If yours are wild, maybe cut it back. I run a sump, no plants, just driftwood. They dig it.

jiffix wrote: ↑Mon May 05, 2025 10:22 am Yo, my crew chills at 50 ppm, no probs. But they're tank-raised beefheart junkies. If yours are wild, maybe cut it back. I run a sump, no plants, just driftwood. They dig it.

Wild Discus would stress at 50 ppm. Domestics are hardier, but long-term health risks include stunted growth. I'd aim for under 30 ppm with planted tanks—Amazon swords help suck up nitrates.

Mine are at 25 ppm with weekly 30% changes. They seem okay, but I notice less color vibrancy compared to when nitrates were lower. Using RO water now to dial it back.

Nitrate tolerance depends on age. Juveniles need under 20 ppm for proper development. Adults can handle 30–40 ppm if other params are pristine. Test your tap—sometimes the source is the culprit. My tap's at 10 ppm, so I'm fighting an uphill battle with water changes alone.

Sketchy to push past 30 ppm, imo. My dude's tank hit 50 once, and they got real lethargic. Backed it down to 20 with more plants, and they perked up. Java fern FTW.

Weird vibe at 40 ppm for me. They ate fine but had fin clamping. Dropped to 15 ppm with double water changes, and it cleared up. Running a sponge filter with peat granules now.

thart wrote: ↑Mon May 05, 2025 1:03 pm Nitrate tolerance depends on age. Juveniles need under 20 ppm for proper development. Adults can handle 30–40 ppm if other params are pristine. Test your tap—sometimes the source is the culprit. My tap's at 10 ppm, so I'm fighting an uphill battle with water changes alone.

Spot on. Also, consider tankmates—tetras poop a ton. I keep mine at 25 ppm with a UV sterilizer and floating plants. Duckweed's messy but works.

Back in my day, we didn't even test nitrates. Fish either lived or died. Now I keep 'em at 20 ppm with a canister and pothos roots in the HOB. Works a charm.