noise...meaning a whole bunch of stuff that junks up the view, like this one.
an aerator stone helps dissolv i (oxygen) in the aquarium
hiya, can you please remove the affiliate tag from the link? (it's the tag= bit, but safest option is to post a clean link, like this: https://www.amazon.com/AquaView-2-5-Gallon-Lighting-Power-Filter/dp/B0083S5PI8/).
(affiliate amazon links are links where if someone buys the product via that link, the affiliated user get's some money. They're often used by content creators or influences, but we don't want random people profiting off of our users)