Suzie-Q wrote:
Should a freshwater aquarium have a smell?

Yes. It's a gentle smell - like a pond or damp earth. It should not
smell fishy and never "foul."

Sometimes I get a "stale" smell coming from my 2.5-gallon betta aquariums.
And I sometimes get a foul smell from my 10-gallon aquarium (a dozen glo-light
and neon tetras, a pleco, a SAE, and about four ghost shrimp).

Clean more and feed less. Leftover food or dead critters will foul a
tank. Add some hornwort or anacharis - plants always help and your
pleco won't do too much damage to floating plants. If he's a common
pleco, he's going to outgrow a 10 gallon tank.

I vacuum the tank and do water changes, although probably not as often as
I should. I've also started using distilled water, since our local tap water
is very hard and God only knows what's in it! (I won't drink the stuff.)

Mix in some tapwater with the distilled so your pH doesn't crash. 1/3
hard tapwater should do the trick.

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