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why is discus tank always murky?
Posted: Thu May 15, 2025 6:04 pm
by Honey
My discus tank has been cloudy for weeks now. I do weekly 50% water changes, use a Fluval 407 canister filter, and keep the temp at 84°F. Tank is 75 gallons with 6 discus, some cardinal tetras, and a few corydoras. Substrate is sand, and I have some driftwood and Amazon swords. Parameters are 0 ammonia, 0 nitrite, 10 nitrate. What am I missing?
Re: why is discus tank always murky?
Posted: Thu May 15, 2025 6:37 pm
by gurer
Sounds like a bacterial bloom, mate. Happens when the bio load spikes or the filter media isn't cycled right. How old is the tank? Also, what's your feeding routine like? Overfeeding can mess with water clarity big time.
Re: why is discus tank always murky?
Posted: Thu May 15, 2025 8:06 pm
by Dory
Honey wrote: ↑Thu May 15, 2025 6:04 pm
My discus tank has been cloudy for weeks now. I do weekly 50% water changes, use a Fluval 407 canister filter, and keep the temp at 84°F. Tank is 75 gallons with 6 discus, some cardinal tetras, and a few corydoras. Substrate is sand, and I have some driftwood and Amazon swords. Parameters are 0 ammonia, 0 nitrite, 10 nitrate. What am I missing?
Your setup seems solid, but cloudiness can come from fine particles in the sand or organics from the driftwood. Try rinsing your filter media in tank water and see if that helps. Also, how often do you vacuum the substrate?
Re: why is discus tank always murky?
Posted: Thu May 15, 2025 9:50 pm
by bowsar
Yep, bacterial bloom is likely. I had the same issue in my 55-gallon. Added a UV sterilizer and it cleared up in days. Also, cut back on feeding for a bit. Discus don't need as much as you'd think.
Re: why is discus tank always murky?
Posted: Thu May 15, 2025 11:17 pm
by guyah
Check your filter flow rate too. A Fluval 407 might not be enough for a 75-gallon with that many fish. I run two filters on my 90-gallon to keep things crystal clear. Also, how old is your filter media? If it's too old, it might not be trapping particles effectively.
Re: why is discus tank always murky?
Posted: Fri May 16, 2025 12:13 am
by theGorilla
I'd second the UV sterilizer idea. Worked wonders for me. Also, maybe add some purigen to your filter. That stuff's magic for clearing up water.
Re: why is discus tank always murky?
Posted: Fri May 16, 2025 1:37 am
by bloom
guyah wrote: ↑Thu May 15, 2025 11:17 pm
Check your filter flow rate too. A Fluval 407 might not be enough for a 75-gallon with that many fish. I run two filters on my 90-gallon to keep things crystal clear. Also, how old is your filter media? If it's too old, it might not be trapping particles effectively.
Spot on. Flow rate is key. I'd also suggest checking if your sand is stirring up too much. Some sands are super fine and can cloud the water if disturbed. Maybe switch to a coarser grade if that's the case.
Re: why is discus tank always murky?
Posted: Fri May 16, 2025 2:31 am
by swiftly
How's your lighting? Too much light can cause algae blooms, which might look like cloudiness. I keep my lights on for 6 hours max and use a timer to avoid overdoing it.
Re: why is discus tank always murky?
Posted: Fri May 16, 2025 4:13 am
by buzzit
Could be a combo of things. I'd start with a deep clean of the filter and substrate. Then maybe add some Seachem Stability to boost the beneficial bacteria. Also, how often do you clean the glass? Algae buildup can contribute to a murky look.
Re: why is discus tank always murky?
Posted: Fri May 16, 2025 4:58 am
by fixin
The cloudiness is likely due to suspended organic particles. Increase mechanical filtration by adding a fine filter pad or polishing pad to your Fluval 407. Ensure you're not overfeeding and remove any uneaten food promptly.