nitrate spikes in coral tank issues

LPS, SPS and all coral chat
flambo0
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Joined: Thu Oct 10, 2024 7:24 pm

nitrate spikes in coral tank issues

Post by flambo0 »

My nitrate levels shot up to 40 ppm overnight in my 75-gallon mixed reef. Running a Red Sea Reefer with two AI Hydra 32s, weekly 10% water changes, and a Reef Octopus skimmer. Corals look stressed, especially the Acropora. Any ideas what's causing this?
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buzznut
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Joined: Thu Oct 10, 2024 5:11 am

Re: nitrate spikes in coral tank issues

Post by buzznut »

Yo, that's sketchy. Did you check your RODI water? Sometimes the filters go bad and dump nitrates. Also, how old's your live rock? Old rock can leach nasties.
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flinta
Posts: 48
Joined: Sat Mar 05, 2022 1:32 am

Re: nitrate spikes in coral tank issues

Post by flinta »

Overfeeding's a common culprit. What's your feeding routine like? I had a similar issue when I was dumping too much Reef Roids into my 60-gallon.
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skylark
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Joined: Fri Aug 25, 2023 4:24 am

Re: nitrate spikes in coral tank issues

Post by skylark »

flambo0 wrote: Wed Apr 30, 2025 3:43 pm My nitrate levels shot up to 40 ppm overnight in my 75-gallon mixed reef. Running a Red Sea Reefer with two AI Hydra 32s, weekly 10% water changes, and a Reef Octopus skimmer. Corals look stressed, especially the Acropora. Any ideas what's causing this?
Have you tested your source water? Sometimes municipal supplies spike nitrates seasonally. Also, check your skimmer's cup—if it's full, it might not be pulling waste efficiently.
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novafx
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Joined: Wed Feb 09, 2022 8:03 am

Re: nitrate spikes in coral tank issues

Post by novafx »

I'd double-check your bio-load. How many fish are in there? Tangs and anthias are nitrate factories if you're overstocked.
flambo0
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Joined: Thu Oct 10, 2024 7:24 pm

Re: nitrate spikes in coral tank issues

Post by flambo0 »

Thanks for the suggestions. I'll test my RODI and cut back feeding. Didn't think about the skimmer cup—it's pretty full.
dawnlite9
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Joined: Thu Oct 10, 2024 7:31 pm

Re: nitrate spikes in coral tank issues

Post by dawnlite9 »

If it's a sudden spike, consider a water change with fresh salt mix. I use Tropic Marin Pro and it's kept my nitrates stable in my 120-gallon.
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haven_9
Posts: 26
Joined: Sat Apr 22, 2023 7:47 am

Re: nitrate spikes in coral tank issues

Post by haven_9 »

buzznut wrote: Wed Apr 30, 2025 4:34 pm Yo, that's sketchy. Did you check your RODI water? Sometimes the filters go bad and dump nitrates. Also, how old's your live rock? Old rock can leach nasties.
For real, man. My RODI unit was the culprit last year. Swapped the DI resin and it fixed everything.
Slice
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Joined: Mon Jun 26, 2023 6:35 pm

Re: nitrate spikes in coral tank issues

Post by Slice »

Test phosphate levels. High phosphates can mask nitrate issues by inhibiting coral uptake. Use a Hanna checker for accuracy.
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Fluxcore
Posts: 6
Joined: Mon Jan 08, 2024 12:13 am

Re: nitrate spikes in coral tank issues

Post by Fluxcore »

Dude, your skimmer might need a tune-up. My Reef Octopus was acting up last month and nitrates crept up. Cleaned the venturi and it's back to pulling gunk like a champ.
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