Filter cycling issues

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Astralove
Posts: 6
Joined: Thu Aug 15, 2024 12:57 pm

Filter cycling issues

Post by Astralove »

My tank's been cycling for three weeks now, but the ammonia levels won't drop below 1 ppm. I'm using a sponge filter and added FritzZyme a week ago. Anyone else had this issue?
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barkwood
Posts: 6
Joined: Wed Feb 01, 2023 5:24 am

Re: Filter cycling issues

Post by barkwood »

What's your tank size and water change routine? Sometimes overfeeding or dead plant matter can keep ammonia high. Also, check if your test kit's expired.
wheelbob
Posts: 1
Joined: Thu Oct 10, 2024 8:24 pm

Re: Filter cycling issues

Post by wheelbob »

Yep, had the same weird vibe with my 20-gallon last month. Turned out my tap water had chloramines, which messed with the cycle. Try Seachem Prime if you haven't already.
MorningBreeze
Posts: 4
Joined: Thu Oct 10, 2024 9:37 pm

Re: Filter cycling issues

Post by MorningBreeze »

wheelbob wrote: Thu Jun 26, 2025 11:14 am Yep, had the same weird vibe with my 20-gallon last month. Turned out my tap water had chloramines, which messed with the cycle. Try Seachem Prime if you haven't already.
Seconding Prime. It's a lifesaver for neutralizing chloramines.
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bricklane
Posts: 3
Joined: Thu Oct 10, 2024 1:25 am

Re: Filter cycling issues

Post by bricklane »

Mate, if your sponge filter's new, it might just need more time. My 10-gallon took a full month to cycle, even with bacteria starters. Patience is key, innit?
flutista
Posts: 6
Joined: Thu Oct 10, 2024 3:47 pm

Re: Filter cycling issues

Post by flutista »

Lol, my betta tank cycled faster than my ex moved on. But seriously, maybe toss in some floating plants? They suck up ammonia like crazy.
marinero
Posts: 5
Joined: Tue May 07, 2024 9:30 am

Re: Filter cycling issues

Post by marinero »

Three weeks ain't too long, but if you're worried, grab a bottle of Tetra SafeStart. Used it in my nano reef and it kicked things off proper.
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Sunflora
Posts: 4
Joined: Wed May 01, 2024 4:56 am

Re: Filter cycling issues

Post by Sunflora »

Have you checked nitrites? If they're rising, the cycle's working, just slow. My goldfish tank took five weeks once. Hang in there!
duskys
Posts: 2
Joined: Thu Oct 10, 2024 7:16 pm

Re: Filter cycling issues

Post by duskys »

Sunflora wrote: Thu Jun 26, 2025 1:48 pm Have you checked nitrites? If they're rising, the cycle's working, just slow. My goldfish tank took five weeks once. Hang in there!
Yeah, nitrites are the real tell. If they're zero, something's sketchy with your bacteria.
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storm9
Posts: 21
Joined: Sun Mar 20, 2022 12:36 pm

Re: Filter cycling issues

Post by storm9 »

Cut it with the bacteria starters and let nature do its thing. Overdosing can stall the cycle. Just my two cents.
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