Are there live plants?
And when was the last time you cleaned the tank?

 

It's a new tank. Just put him in Saturday. Then Sunday the strange smell emerged. Plants, yes but they are healthy.

 

All tanks have a smell, but it is a very earthy and subtle scent. If you're smelling anything strong or sour then you have a problem. If you have a very compact substrate, for instance, pockets of anaerobic bacteria may build up and then when they are released, they come to the surface as a nasty smell. If you are changing your water, rinsing your filter media, and cleaning your gravel properly, then you should not have any odor. Are you adding any chemicals to the water? Some dechlorinators have a strong smell (Prime smells TERRIBLE) but it should dissipate very quickly once it's been added to the water.

 

Since I said the smell was... noticeable, different, but not bad... it must not be a bad smell then... *Sighs relief* When I go back home this weekend I'll check to see if the smell has gone away or gotten stronger. Mom didn't mention it today when feeding Drax so maybe it's gone now.

Good news is she finally got Drax to eat a few pellets... or so she thinks she did... She says he's not bloated or anything (She doesn't know much about fish but she knows enough to follow instructions, plus she's a mom haha she has 'That doesn't look right' Senses haha)... I think he's just being a pest honestly...

 

Like others have said it depends on the smell. If it smells swampy/gross then it means you need to do more frequent water changes. If it just smells earthy like a lake or river it's just healthy. If it smells chemically it may just be your conditioner.

All tanks have bacteria which emit odours, the bad ones will make you cringe or feel ill since your instinct is to get away from harmful bacteria. If it's just different but not exactly unpleasant then it is the good bacteria happily doing their jobs.

 

Probably the Conditioner then... Since it's........... Earthy (Trying to recall smell) yet... Vaguely chemical.