but now you need to understand it for your fish tank bro
starting a good fish tank can be as hard as preventing root rot IMO
i remember a fish tank needing stuff to help complete the waste-management cycle when it is first setup, and then once it gets going the good bacteria will stay and live in ceramic disc thingies.
here's a cute photo on the nitrogen cycle in a fish tank. it's cool stuff, especially stage 2 and 3. when you first start a fresh tank you don't have any of that bacteria that breaks shit down yet, so you add some, or i guess wait it out slowly until they build. idk what kids are doing these days lol. i remember adding a product called "cycle" to help finish the cycle in early tanks
what kinda tank are you running? any fish in it yet?