value of the sniff test.

[andruboz]

just curious on the opinion of aroma and aquariums.
i mean, if your water is stinkin you probably have a problem, but it may not smell at all and still be toxic. does a perfectly healthy tank have just a tiny bit of swamp funk to it? does a planted tank smell better than an all fish tank? do some fish smell worse than others? does anybody do water changes on smell instead of clarity?

[pinballqueen]

I think all tanks have an odor, healthy or otherwise, so doing a "sniff test" is a very bad way to do water changes, IMO. So is a simple clarity test, for that matter. My tanks, whether planted or all-fish, have always had the "swamp funk" you refer to... frankly, I kinda like it...

High-protein demanding fish, like cichlids, will tend to have a stronger odor, especially if you occasionally feed meaty foods like feeders or live worms, but it's not noticeable unless you have another tank of a different type to compare.

Now, if your tank smells like bleach or dog pee or something, that might be a good indicator of a problem....:D

I guess it depends on how good your nose is...

[Ashes]

My mom frequently walks into my room and says "It smells like an aquarium in here."

It makes me laugh...

[Orbitorly]

I used to be able to smell a odor, carbon helps get ride of it. We also have tanks in every room so where used to it.

[125gJoe]

Originally posted by andruboz
..... does anybody do water changes on smell instead of clarity? No. Not me.

I think planted tanks may have more of an 'earthy' smell...

[wetmanNY]

Every once in a while I put 5ccs/10gal. hydrogen peroxide in at the filter outflow. H2O2 oxidizes organics in the water.

There's a "green" pond smell that's like "Mmm! ...chlorophyll-y!"

There's a skanky stale oniony foxy musty smell that comes from thiols (mercaptans) and phenols. Part of decay and renewal. More oxygen oxidizes these odors to non-smelling things such as sulfates.

A farmer smells a handful of soil and knows it needs lime or it doesn't. Don't you get general information from the smell of the tanks?

[GobyGuy5]

I've read that if your fish tank smells like earth shortly after a rain, that it is a sign of a healthy tank...........