Dealing with high nitrates in reef

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redFox33
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Joined: Thu Oct 10, 2024 9:11 pm

Dealing with high nitrates in reef

Post by redFox33 »

My nitrates have been sitting at 30 ppm for weeks now, and my Zoanthids are looking kinda sad. I do weekly 10% water changes, run a protein skimmer, and have a refugium with Chaeto. What else can I try to bring them down?
lumin5
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Joined: Thu Oct 10, 2024 10:30 pm

Re: Dealing with high nitrates in reef

Post by lumin5 »

30 ppm ain't terrible, but it's definitely on the high side for Zoas. You might wanna bump those water changes to 20% weekly. Also, how's your feeding routine? Overfeeding's a sneaky nitrate booster.
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DarkFable9
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Re: Dealing with high nitrates in reef

Post by DarkFable9 »

lumin5 wrote: Wed Aug 20, 2025 12:29 pm 30 ppm ain't terrible, but it's definitely on the high side for Zoas. You might wanna bump those water changes to 20% weekly. Also, how's your feeding routine? Overfeeding's a sneaky nitrate booster.
Agreed. I'd also check your skimmer's output. If it's not pulling much gunk, it might need tuning. What salt mix are you using? Some are nitrate-heavy straight outta the bag.
mountbob
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Joined: Thu Oct 10, 2024 10:26 pm

Re: Dealing with high nitrates in reef

Post by mountbob »

Hey, don't stress too much! Zoas can bounce back once you dial things in. Have you tested your source water? Sometimes tap or even RO/DI can have nitrates. Also, how old's your Chaeto? If it's not growing fast, it's not sucking up much.
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DuskFlyer
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Re: Dealing with high nitrates in reef

Post by DuskFlyer »

I'd throw in some nitrate-absorbing media like Seachem Matrix or Purigen. Works wonders in my 75-gallon. Also, what's your bioload like? Too many fish can overwhelm even a solid filtration setup.
Sakurako
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Joined: Thu Oct 10, 2024 7:58 pm

Re: Dealing with high nitrates in reef

Post by Sakurako »

mountbob wrote: Wed Aug 20, 2025 1:22 pm Hey, don't stress too much! Zoas can bounce back once you dial things in. Have you tested your source water? Sometimes tap or even RO/DI can have nitrates. Also, how old's your Chaeto? If it's not growing fast, it's not sucking up much.
Seconding the Chaeto check. Mine took off once I added a cheap LED grow light. Also, consider vodka dosing—sounds sketchy, but it's a legit nitrate reducer if done right.
fluxon9
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Joined: Thu Oct 10, 2024 7:32 pm

Re: Dealing with high nitrates in reef

Post by fluxon9 »

Before you go dosing anything, maybe try cutting back on feedings for a week. I had a similar issue, and my tank chilled out once I stopped dumping in so much mysis.
Busday
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Joined: Thu Oct 10, 2024 9:10 pm

Re: Dealing with high nitrates in reef

Post by Busday »

Or just get a bunch of hermits and tell 'em it's a buffet. Jokes aside, yeah, overfeeding's the usual suspect. What's your cleanup crew looking like? More snails = less leftover food.
waveset
Posts: 1
Joined: Thu Oct 10, 2024 8:11 pm

Re: Dealing with high nitrates in reef

Post by waveset »

My nitrates were worse, like 50 ppm, until I added a deep sand bed. Took a few months, but now they're steady at 5. Just gotta be patient with some fixes.
redFox33
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Joined: Thu Oct 10, 2024 9:11 pm

Re: Dealing with high nitrates in reef

Post by redFox33 »

Thanks for all the ideas, everyone. Gonna try bigger water changes and cut back on feeding first. Appreciate the help!
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