Help... the smell! Tank with strong odor

CoachMatthews

I’m struggling. My tank has a strong odor. It’s a 29g, it’s slightly overstocked with livebearers, I have dual filters running (70g and 30g), I vacuum substrate 1-2x per week, I maintain the filters, rinse the biomedia and sponges in tank water every month or so, change my activated carbon on schedule, and my water parameters consistently are 0 on ammonia and nitrates, and nitrates are usually at 20-30. I also do weekly water changes, but I have been doing changes 3-4x a week now because that is the only way I can get any respite from the odor. But 2 days later it’s back to full potency. The tank is 5 months old and the strong smell has been in the last month. Any suggestions?

*0 ammonia and nitrites

One more addition... I’m really careful about feeding. I’ve gotten it down pretty well. Over feeding isn’t the issue.
 

YellowGuppy

Do you have any plants? They might freshen things up quite a bit.
 

Dunk2

I’m struggling. My tank has a strong odor. It’s a 29 gallon, it’s slightly overstocked with livebearers, I have dual filters running (70g and 30 gallon), I vacuum substrate 1-2x per week, I maintain the filters, rinse the biomedia and sponges in tank water every month or so, change my activated carbon on schedule, and my water parameters consistently are 0 on ammonia and nitrates, and nitrates are usually at 20-30. I also do weekly water changes, but I have been doing changes 3-4x a week now because that is the only way I can get any respite from the odor. But 2 days later it’s back to full potency. The tank is 5 months old and the strong smell has been in the last month. Any suggestions?

Do you have carbon in your filter?
 

CoachMatthews

Thanks for the response. I have started to plant it more. It was all fake stuff. 2 weeks ago I added two live plants. I want to see how the progress and then will replace more.

yes I do. I change it every two weeks. I could add a carbon bag to the second filter and take out the biomedia from the 30?

Every three weeks I mean.
 

Dunk2

I’d hesitate removing bio media and causing a disruption in your cycle.

Are you sure you don’t have a dead fish? What about driftwood?
 

CoachMatthews

No dead fish. All accounted for thankfully! I do not have driftwood.
 

Dunk2

If you’re running carbon in one of the filters, I can’t imagine you’d have that strong of an odor given the maintenance you describe.
 

StarGirl

Maybe some crud up under the lip of the tank?
 

CoachMatthews

Ya. I feel like I must be missing something, but I have carbon and have been doing anything I can think of. I’m stumped.
 

e_watson09

Odors are not at all normal coming from a tank. How does the filter media look is it super gunked up or does the two filters seem to be doing okay with the bioload? Can you take a picture of the tank? Mostly looking at the decorations and such. Something has to be bringing that smell in and if its not a rotten fish my next guess is something in the filter or decorations. Do you over feed? A build up of extra food in the filter could be the culprit too
 

Dunk2

Thanks for the response. I have started to plant it more. It was all fake stuff. 2 weeks ago I added two live plants. I want to see how the progress and then will replace more.

I was going to ask about snails coming with your plants, but you said the smell was bad before you planted?
 

CoachMatthews

there is a bit. I’ll clean that out. Can’t imagine it all comes from that? But every bit will help I’m sure. Ha
 

StarGirl

there is a bit. I’ll clean that out. Can’t imagine it all comes from that? But every bit will help I’m sure. Ha
When I wipe under mine it is black, crusty and gross. lol I don't know if it has a smell though.
 

CoachMatthews

There is the tank. I’ll post filters in a few minutes.
 

Attachments

  • A262967D-4582-4C9A-8FE9-8B35D9391724.jpeg
    A262967D-4582-4C9A-8FE9-8B35D9391724.jpeg
    94.2 KB · Views: 97

Nobote

Rotten egg or sulphuric smell?
You may have a bacteria producing hydrogen sulphide or sulphur dioxide.
If you have marimo in the aquarium...they can be the culprit.
Organic material trapped in the substrate can do it as well.
 

CoachMatthews

No, no moss balls. However, the smell does smell sulfur-like. I may just totally replace the substrate. It was cheap when I first set up the tank and it seems to break apart easily when I siphon it. Think that’s worth a shot?

Here are the two filters. Fluval c4 and then the smaller one is the one that came with the tank setup.
 

Attachments

  • D482C98D-6791-4E63-89DB-4CA5D7D95161.jpeg
    D482C98D-6791-4E63-89DB-4CA5D7D95161.jpeg
    48.2 KB · Views: 64
  • CE2FBC22-80CB-4939-832F-25EACBAC84FA.jpeg
    CE2FBC22-80CB-4939-832F-25EACBAC84FA.jpeg
    33.1 KB · Views: 65
  • E1723275-4B9D-48BB-8D6C-AA7FDAA2B42D.jpeg
    E1723275-4B9D-48BB-8D6C-AA7FDAA2B42D.jpeg
    55 KB · Views: 67
  • 889332DC-8DBA-443A-9E9E-BE17EADAFCA4.jpeg
    889332DC-8DBA-443A-9E9E-BE17EADAFCA4.jpeg
    70.7 KB · Views: 71

CoachMatthews

the filter media is pretty clean. Some of it has some blackish spots, but no gunk on it. I definitely overdoes to start. I feel pretty confident that I’m not now. Filters posted below.
 

A201

I agree with StarGirl15 theory. The only time my tanks have ever stink is when food & bio gunk get stuck on & under the rim. The fish also can splash gunk on the underside of the rim. Once the gunk rots, the smell is awful. I routinely wipe down the upper rI'm with every WC.
 

Nobote

If you replace the substrate, clean everything with h202 and 90% ethanol.

How much flow is there? Water moving pretty decent?
 

CoachMatthews

Yes, good flow with bother filters and the bubbler. I may consider the clean out of the substrate. It’s the water itself that has the odor, it’s not coming from my now cleaned out hood.

Maybe this is the issue and I’m just a big rookie... when I clean my filter I typically just rinse the sponge really well under hot water. (Assuming that the BB in the biomedia can more than make up for cleaning the sponge with tap water?) I don’t actually replace the sponge pad itself. I have had the same one for five months. I just changed that out now. Could that be it?
 

Wardonianfungus

No, no moss balls. However, the smell does smell sulfur-like. I may just totally replace the substrate. It was cheap when I first set up the tank and it seems to break apart easily when I siphon it. Think that’s worth a shot?

Here are the two filters. Fluval c4 and then the smaller one is the one that came with the tank setup.
That’s what I had to do. My whole house smelled like a pond for three weeks until I did.
 

Nobote

Your sponge is living. Its a bacterial colony. If you're rinsing in hot water you're cooking the bacterial colony.
 

CoachMatthews

Yep. I get that, but I also have a second sponge and two filters packed with biomedia. I assumed/ was advised that the difference was negligible. Certainly open to differing views on that though.
 

KribensisLover1

How overstocked is it? It didn’t look that crazy. You poor thing that’s awful. Could he take the lid off and air it out? I am new sorry I don’t know.
 

Nobote

I would stop rinsing sponges in hot water.
I believeyou have plenty of media filtration to survive killing a sponge, but you're essentially resetting instead of leaving it colonized, which is counterproductive.
 

CoachMatthews

There are a lot of corys in there.
How overstocked is it? It didn’t look that crazy. You poor thing that’s awful. Could he take the lid off and air it out? I am new sorry I don’t know.
 

Redshark1

A well balanced tank should not have any bad smell and should smell sweet like you could happily drink the water. Don't though! Maybe that's going a bit far but you get what I mean.

If you rinse your sponges / biomedia in hot water you will kill your beneficial bacteria and dead bacteria will decompose and stink.

Otherwise you seem to be tackling things thoughtfully. Your tank looks good, very clean and new but not mature. I never had problems with natural gravel. I assume the water source is good and it is being treated e.g. with Prime.

I would check that there is no organic matter anywhere like on the cover glass etc. and make sure you are not spilling water accidentally. The bad smell points to damp and decay somewhere. Maybe take a sample of water out and a sample of gravel to test smell them away from the tank.

Ornaments, especially hollow ones can produce a stink.

If it really is just the water then you may have to attend to feeding (your fish need only 2 flakes each per day) and any overstocking. However, your parameters do not suggest anything wrong and fish are not dying. Some people are more sensitive to smells.
 

CoachMatthews

Update... it’s been over 36 hours since I packed my second filter with carbon. Took a bit, but woke up this morning to a distinct LACK of pond smell in my family room. Fish seem happy and water numbers still looking strong, nitrate even down a bit. Woo! Thanks all.
 

Redshark1

I never use Carbon.

Keep working on it. You can always improve your water. Never stop trying to improve.

I find ways every year. I'm now in my 50th year of fishkeeping and I found major ways to improve my aquaria this year too.
 

Similar Aquarium Threads

Replies
17
Views
700
FishBeans
Replies
5
Views
505
kallililly1973
Replies
30
Views
2K
RonJ
Replies
7
Views
503
angelcraze
Replies
20
Views
2K
Bighead

Latest Aquarium Threads

Top Bottom