You'd need a BIG tank to do it. I'm talking 5-6 thousand gallons if you want fish in it. You can make a 5 gallon sealed unit using algae & a few tiny shrimps.
What you're thinking about is called "the dynamic aquarium." googling that name will show you some stuff.
The small sealed unit version is called a "geniscycle" and you can probably still buy one on the internet somewhere.
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