discus tank water change timing

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SunnyG
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Joined: Fri Apr 14, 2023 5:41 am

discus tank water change timing

Post by SunnyG »

How often do you guys change water for your Discus? I've got a 75-gallon tank with 6 juveniles, sand substrate, and a canister filter. Been doing 30% every 3 days but they seem stressed after. Temp's at 84°F, pH 6.8. Maybe I'm overdoing it?
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Bolden
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Joined: Tue Aug 29, 2023 4:34 pm

Re: discus tank water change timing

Post by Bolden »

30% every 3 days is solid for juvies, but stress could mean the new water's off. Check if your tap matches tank params—temp, pH, hardness. I use a mixing valve to pre-heat, and Prime to neutralize chlorine. Also, how's your flow rate? Too fast can freak them out.
cadence
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Joined: Sat Apr 27, 2024 11:34 pm

Re: discus tank water change timing

Post by cadence »

yo, same setup here! i do 25% every other day but drip the new water in over an hour. keeps things steady. also, my discus dig the dim lights during changes. try blackout curtains, it's a vibe.
vital
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Joined: Thu Feb 23, 2023 5:40 pm

Re: discus tank water change timing

Post by vital »

Bolden wrote: Mon Aug 11, 2025 7:57 am 30% every 3 days is solid for juvies, but stress could mean the new water's off. Check if your tap matches tank params—temp, pH, hardness. I use a mixing valve to pre-heat, and Prime to neutralize chlorine. Also, how's your flow rate? Too fast can freak them out.
Agreed. My tap's pH is 7.4, so I buffer with peat moss in a storage barrel. Takes 24 hrs to stabilize. Also, are you vacuuming the sand? Waste buildup can spike nitrates fast.
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knight
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Re: discus tank water change timing

Post by knight »

I'd cut back to 20% changes if they're stressed. Mine are adults in a 125-gallon, planted with driftwood. Weekly 40% works fine, but juvies need more. Maybe skip a change and observe? Sometimes they just need a chill week.
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SunnyG
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Joined: Fri Apr 14, 2023 5:41 am

Re: discus tank water change timing

Post by SunnyG »

Thanks, all! Gonna test my tap and slow the flow. Didn't think about the lights—good call.
Seadog
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Joined: Wed Aug 02, 2023 1:00 pm

Re: discus tank water change timing

Post by Seadog »

Stress post-change could also be osmotic shock. What's your TDS? I aim for under 100 ppm for juvies. RO water helps, but remineralize with Equilibrium. Also, how's their appetite? If they're eating beef heart after, it's probably not the change itself.
landfall
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Joined: Thu Oct 10, 2024 3:40 pm

Re: discus tank water change timing

Post by landfall »

mixing valve's a game-changer, like Bolden said. i rigged mine with a cheap inline heater. also, try aging the water 12 hrs with an airstone—lets gases off-gas. my discus stopped glass surfing after i started that.
mander
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Joined: Fri Mar 22, 2024 8:41 pm

Re: discus tank water change timing

Post by mander »

cadence wrote: Mon Aug 11, 2025 9:16 am yo, same setup here! i do 25% every other day but drip the new water in over an hour. keeps things steady. also, my discus dig the dim lights during changes. try blackout curtains, it's a vibe.
Dripping's key. I use a 5-gallon bucket and airline tubing with a valve. Takes 2 hrs for 10 gallons, but zero stress. Also, check your water change tool—gravel vacs can suck up sand and stir debris.
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tonic
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Joined: Mon Aug 15, 2022 2:35 pm

Re: discus tank water change timing

Post by tonic »

Anyone else notice seasonal changes affect this? My discus hate winter water—extra skittish. I warm the storage barrel to 86°F December–March. Summer's easier, just match room temp.
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