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What's the best water flow setup for a 75 gallon Discus tank? I've got a Fluval FX4, but I'm worried it's too strong. They're juveniles, about 3 inches, and seem stressed when the flow's high. Tankmates are cardinal tetras and corydoras. Substrate is sand, with some driftwood and java fern. Water params are good, 0 ammonia, 0 nitrite, 10 nitrate. Temp's at 84°F. Should I baffle the output or switch to a gentler filter?

The FX4 is a beast for a 75 gallon, especially with juvies. I'd start by baffling the output with a sponge or adjusting the flow valve if it's got one. My Discus hated strong flow until they hit 5 inches. I run an Eheim 2217 on my 90 gallon, and they're chill with it. How often are you doing water changes? With sand, you gotta watch for dead spots.

Dodge wrote: ↑Tue Jul 08, 2025 10:08 pm The FX4 is a beast for a 75 gallon, especially with juvies. I'd start by baffling the output with a sponge or adjusting the flow valve if it's got one. My Discus hated strong flow until they hit 5 inches. I run an Eheim 2217 on my 90 gallon, and they're chill with it. How often are you doing water changes? With sand, you gotta watch for dead spots.

Yep, baffle it. I've got a DIY sponge on my FX6, and my Discus stopped hiding. Also, try pointing the output at the glass to diffuse the flow. Sand's tricky, so maybe add a wave maker for circulation? My tank's bare bottom, but I've seen sand work with extra flow tweaks.

I'd ditch the FX4 for now. Go with a pair of smaller filters, like two AquaClear 70s. Spreads the flow better, and you can adjust each one. My Discus tank's planted, with CO2, and the dual filters keep things steady. Temp's at 86°F, and they're breeding. Sand's fine if you've got enough flow to prevent buildup. How's your feeding routine? Overfeeding with high flow can mess with the sand.

Strong flow stresses juvies, but adults need more. I'd baffle the FX4 and add a small powerhead for circulation. My 75 has a Seachem Tidal 55 and a Hydor Koralia nano. Substrate's pool filter sand, and I vacuum it weekly. Discus are 4 inches now and handle the flow fine. What's your lighting schedule? Too much light with high flow can freak them out.

My Discus tank's got a canister and a sponge filter. Flow's gentle, and they're always out. Sand's a pain, but I stir it during water changes. Tank's 55 gallons, with driftwood and anubias. Temp's 82°F. Maybe try a sponge filter if the FX4's too much? They're cheap and easy to tweak.

Baffling's the way to go. I use a pre-filter sponge on my FX4's output, and my Discus are way happier. Tank's 75 gallons, sand substrate, with vals and swords. Flow's still strong enough to keep the plants swaying gently. Water changes are 30% twice a week. How's your pH? Stable flow helps keep it steady.

I've got a similar setup, 75 gallon with sand and an FX4. Baffled the output with a spray bar, and it's perfect now. Discus are 5 inches, with rummynose tetras. Temp's 85°F. Spray bar's DIY, just PVC with holes drilled in it. Cheap fix if you're handy.

Anyone tried a wavemaker with Discus? I've got a Jebao in my 90, but I'm scared it's too strong. Tank's bare bottom, with a few pieces of driftwood. Discus are adults, about 6 inches. Flow's adjustable, but I'm not sure where to set it.

hype wrote: ↑Wed Jul 09, 2025 3:51 am Anyone tried a wavemaker with Discus? I've got a Jebao in my 90, but I'm scared it's too strong. Tank's bare bottom, with a few pieces of driftwood. Discus are adults, about 6 inches. Flow's adjustable, but I'm not sure where to set it.

I run a Jebao on low in my 120, and the Discus don't mind. Key is to keep it subtle. Tank's got sand and some crypts. Flow's just enough to keep the plants moving. Maybe start at the lowest setting and bump it up slowly?