Aquarium smell

Aquarium Smell – Why and How To Fix It (Quick & Slow Way)

Your fish tank should not smell bad! There’s a reason for Aquarium smell and it has more to do with your maintenance than it does with your fish.

For those of you looking for the quick fix add some activated carbon to your filter and that smell will be gone over night. But for those of you that understand something in your tank is causing this funky smell, I’m going to tell you what’s most likely causing it and how to prevent it so you don’t have to use activated carbon if you don’t want to!

Activated carbon is great at removing odors from your tank, removing medications from your tank and also helps a lot in making your water look crystal clear. But activated carbon is a chemical media that needs to be replaced about every month or so. If not it can actually leach out all the nasty’s that it’s absorbed right back into your tank. The cost of replacing that every month along with everything else we spend in this wonderful hobby can quickly add up.



What should An Aquarium Smell Like

Honestly, it should smell like nothing. Sure if you stick your nose right above your water you may get a soft stench of sulfur or fishyness. But overall your tank should not stink.

The room where your tank is located should not have any foul odor. When you have company they should not know you have an aquarium until they see your beautiful tank and fish!

Why Aquarium Smell In House

So besides putting a band aid on the issue with chemical media, lets talk about the underlying reason why your tank smells like some hard boiled eggs left out in the sun all day.

Your tank smells because of the decomposing organic matter in your tank. It’s really that simple. If you get that decomposing matter out of your tank you’ll eliminate 90% of the stench.


Dead Fish Causing Aquarium Smell

The number 1 decomposing matter causing a bad smell is usually dead fish. Has it been a while since you’ve seen little Johnny? Well you may want to move some décor around and make sure his dead body isn’t trapped in your tank, decomposing away and causing your entire living room to smell like a sewer.

If you cant find Johnny, keep in mind that he may have been eaten by his comrades but some small parts of him could be stuck somewhere.


Fish Waste Causing Aquarium Smell

Number 2 reason your tank smells is because our fish poop, and it stinks! Obviously right. Well if you’re allowing a lot of fish waste to build up in your tank, you guessed it. It’s going to make your tank stink.

Scheduled water changes and vacuuming of your substrate will help reduce this waste build up. I’ve said this before and I’ll say it again. This hobby is not for the lazy.

When we get lazy our fish suffer, tank looks nasty, and it’ll eventually smell nasty too. But how often should we do water changes, or when do we know it’s time for a water change?

The indications will come well before your tank starts to stink. This video playlist will help you set up a solid maintenance schedule.


Dirty Filters Causing Aquarium Smell

Lets not forget our filters. We can water change and vacuum as frequently as we can to try and get the smell out, but without filter cleanings we’ll never climb out of that hole.

Filter cleanings should be done on a schedule as well because the trapped poop and gunk in your filters will also eventually release those stinky gasses in to your tank water and then out into your living space.

I know your next question, how often should you clean your filter? Answer is right here!


Over Feeding Causing Aquarium Smell

Another huge reason that should be at the top of the list is you’re overfeeding the tank.

By over feeding, your fish are going to eat more….which means they’re going to poop more…and we already discussed that.

But uneaten food can cause many problems in your tank. From ammonia spikes, to cloudy water, to stinky smell as well. As the uneaten food decomposes, bacteria eat those dissolved organics and their poop stinks too.

Just did an entire video on these type of bacteria and the cloudy water they could cause in your tank, watch here.


Dead Plants Causing Aquarium Smell

Dead plants can also cause an odor in your tank. Sometimes they can go unnoticed if you have a heavily planted tank, but finding and removing them will eliminate the smell as well.


How To Remove Aquarium Smell

The premise here is that any decomposing matter in your tank, whether its dead bodies, uneaten food, dead plants or excess fish waste will all contribute to a bad aquarium smell.

By removing that decomposing organic matter with your scheduled maintenance, water changes, vacuuming, and filter cleanings, you will eliminate that bad aquarium smell. Adding activated carbon to your filter can also help in quickly, but temporarily, removing the smell.

Don’t blame your tank and fish for stinking up your place, the thing to blame here is you. Granted some of you are new to the hobby and were just unaware, ok, you guys get a pass.

But for the rest of you, tisk tisk. I know I may sound harsh but I’m here to give it to you straight, I’ll always give it to you like it is. I’m pointing the finger at you. So get to work 😊

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