Bad Aquarium Smell

Hey there!

I've recently noticed that my 20-gallon tank has had a gag-worthy smell lately. It's not overstocked, just a few tetras etc., the parameters are balanced, I'm not overfeeding them (I have cut down on the food since I started smelling it), cleaned the filter, the temperature is a stable 78 degrees, fish are super happy and active and it is not ammonia poisoning.

What I have noticed is that I left the light on for a bit more than 8 hours every day sub-consciously and some algae has started to form on the driftwood. No idea if that would create such a bad smell, but that was something that has been a change within the last few days/week.

Let me know if you know the cause and if you know how to treat it! Thanks.

 

How often do you change the water? It can probably be from not changing the water enough.
Can you post a picture of the algae?

 

What kind of driftwood? It could be rotting. Sure you’re not overfeeding because that was always my smell problem. Have any snails or anything? Those things will die and you won’t know it until the smell.

 

What kind of driftwood? It could be rotting. Sure you’re not overfeeding because that was always my smell problem. Have any snails or anything? Those things will die and you won’t know it until the smell.

I only put the driftwood in about 1 1/2 weeks ago after I removed the tannins from it - I doubt it would be rotting, but it's still a possibility. I only have maybe 4 tiny snails that are just there to keep the algae down, not enough to smell up the entire tank if they did die. I just recently had a mystery snail die in one of my other tanks and it is a completely different smell... I'll be sure to keep an eye on the feeding though.

How often do you change the water? It can probably be from not changing the water enough.
Can you post a picture of the algae?

Average amount, about once per week. Sadly, I'm not able to get a picture right now. But, it is about 1cm tall and it sways with the current. I know that's a terrible way of describing it, but it's the best I can do, lol.

 

So what you are describing sounds like phenols. They cause that "fish tank smell" they are aromatics but not the ones you want. Easiest way to get rid of that, (and I hate saying this) carbon in your filter or carbon in a mesh bag with water flow across it. It is one of the only actual useful functions of the carbon garbage but it does work for this. After the smell is gone then you should be a little more regimented in your lighting routine which should lessen the effect.

 

Do you use bio balls or anything in your filter that can add helpful bacteria?

 

Can you describe the smell? Earthy? A fart? Ammonia smells like burning/burnt. Driftwood can get kinda funky if it is new because it can grow fungus (which most snails will eat and it will naturally go away on its own). A tank should not smell fishy or rank. Most tanks have a slight wet leaf/dirt smell to them, even ones with fake plants (has to do with the breakdown of fish poop), but they shouldn't stink.
Prime has a rotten egg/sulfur smell sometimes (depending on if it gassed off during pouring or it just got poured into the tank).
The algae may be BBA which looks sort of grass like in its movements/color/shape.

 

Can you describe the smell? Earthy? A fart? Ammonia smells like burning/burnt. Driftwood can get kinda funky if it is new because it can grow fungus (which most snails will eat and it will naturally go away on its own). A tank should not smell fishy or rank. Most tanks have a slight wet leaf/dirt smell to them, even ones with fake plants (has to do with the breakdown of fish poop), but they shouldn't stink.
Prime has a rotten egg/sulfur smell sometimes (depending on if it gassed off during pouring or it just got poured into the tank).
The algae may be BBA which looks sort of grass like in its movements/color/shape.

To be honest, I'd describe the smell as a very earthy fart, lol. I can see what you're saying about the wet leaf/dirt smell - it smells like that but escalated.

So what you are describing sounds like phenols. They cause that "fish tank smell" they are aromatics but not the ones you want. Easiest way to get rid of that, (and I hate saying this) carbon in your filter or carbon in a mesh bag with water flow across it. It is one of the only actual useful functions of the carbon garbage but it does work for this. After the smell is gone then you should be a little more regimented in your lighting routine which should lessen the effect.

Thank you very much! I'll definitely look into that.

 

To be honest, I'd describe the smell as a very earthy fart, lol. I can see what you're saying about the wet leaf/dirt smell - it smells like that but escalated.

water changes and carbon are best ways to combat smells - carbon works well for smells as it absorbs them.

 

water changes and carbon are best ways to combat smells - carbon works well for smells as it absorbs them.

Fantastic. I appreciate your help.