discus tank water change frequency

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Lavida
Posts: 17
Joined: Thu Oct 10, 2024 3:33 pm

discus tank water change frequency

Post by Lavida »

How often do y'all change water for your Discus? I got a 75 gallon tank with 6 adults, sand substrate, and a Fluval canister filter. Been doing 30% weekly but they seem stressed after. Water's at 84°F, pH 6.8, 0 ammonia, 0 nitrite, 10 nitrate. Maybe I'm messing with them too much?
brites
Posts: 12
Joined: Thu Aug 03, 2023 2:33 am

Re: discus tank water change frequency

Post by brites »

With adults in a 75, you can cut it back to 20% weekly if params stay stable. Key is consistency, not volume. I do 15% twice a week in my 90 gallon, same temp and pH as yours, with driftwood and Java fern. Less shock that way.
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Blazer
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Joined: Fri May 20, 2022 3:59 pm

Re: discus tank water change frequency

Post by Blazer »

Mine hated big changes too. Switched to 10% every 3 days and they chilled out. Using Seachem Prime, sponge filter, no plants. Tank's bare bottom though, which might make a diff.
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Kargo
Posts: 23
Joined: Thu Feb 10, 2022 9:44 pm

Re: discus tank water change frequency

Post by Kargo »

Lavida wrote: Fri Aug 15, 2025 6:57 am How often do y'all change water for your Discus? I got a 75 gallon tank with 6 adults, sand substrate, and a Fluval canister filter. Been doing 30% weekly but they seem stressed after. Water's at 84°F, pH 6.8, 0 ammonia, 0 nitrite, 10 nitrate. Maybe I'm messing with them too much?
Stress could be from temp or pH swings during changes. Try matching new water to tank temp within 1°F and pre-treating with Prime. My group in a planted 120 gets 25% weekly, aged water only.
Ticgo
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Joined: Thu Oct 10, 2024 3:33 pm

Re: discus tank water change frequency

Post by Ticgo »

Weird vibe, mine love fresh water! 50% weekly in a 55 with pool filter sand and a HOB. They crowd the siphon like it's feeding time. Maybe your flow's too strong during changes? I trickle refill over an hour.
Luxury
Posts: 18
Joined: Mon Dec 18, 2023 2:58 pm

Re: discus tank water change frequency

Post by Luxury »

Aight, real talk, if they're hiding after changes, something's sketchy. Test your tap for chloramines or metals. My crew gets RO mixed with tap, 20% every 5 days, with almond leaves. Eheim heater keeps it steady at 86°F.
Lavida
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Joined: Thu Oct 10, 2024 3:33 pm

Re: discus tank water change frequency

Post by Lavida »

Thanks for the tips! Gonna try smaller, more frequent changes and check my tap. Didn't think about the refill speed.
brites
Posts: 12
Joined: Thu Aug 03, 2023 2:33 am

Re: discus tank water change frequency

Post by brites »

Ticgo wrote: Fri Aug 15, 2025 11:13 am Weird vibe, mine love fresh water! 50% weekly in a 55 with pool filter sand and a HOB. They crowd the siphon like it's feeding time. Maybe your flow's too strong during changes? I trickle refill over an hour.
Interesting! Might depend on strain. My German Heckels are way more sensitive than domestic blues. What variants do you have?
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Kargo
Posts: 23
Joined: Thu Feb 10, 2022 9:44 pm

Re: discus tank water change frequency

Post by Kargo »

Blazer wrote: Fri Aug 15, 2025 8:42 am Mine hated big changes too. Switched to 10% every 3 days and they chilled out. Using Seachem Prime, sponge filter, no plants. Tank's bare bottom though, which might make a diff.
That's a solid middle ground for stressed fish. Just watch nitrates don't creep past 20ppm.
Ticgo
Posts: 22
Joined: Thu Oct 10, 2024 3:33 pm

Re: discus tank water change frequency

Post by Ticgo »

brites wrote: Fri Aug 15, 2025 1:56 pm
Ticgo wrote: Fri Aug 15, 2025 11:13 am Weird vibe, mine love fresh water! 50% weekly in a 55 with pool filter sand and a HOB. They crowd the siphon like it's feeding time. Maybe your flow's too strong during changes? I trickle refill over an hour.
Interesting! Might depend on strain. My German Heckels are way more sensitive than domestic blues. What variants do you have?
Yep, these are cheapo red turqs from a local breeder. Tough as nails. Heckels would probably faint if I sneezed near their tank.
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