I have a hang on the back filter, and I put in these cartridges that come with these packets of activated carbon, so I'm assuming it like a 2in1 so I have a bio-filter and a mechanical filter.
I did not consult with my LFSs about which fish to buy. I didn't want to have a community tank of a lot of small fish (which my brother has), but rather only a few bigger fish. so after spending a couple weeks researching on the web about what kinds of fish fit my criteria, I settled on Oscars and the Eclipse catfish. I actually originally thought about keeping only one tiger oscar, but over time, I started to also really like the sun cat and red oscar
I personally made lots of mistakes in my years of Fish keeping. So I was not perfect in any way lol. Please take time and read the link above and if you have any questions we will help answer them the best way possible.
Do you have Dechlorinator on hand? I'm asking because you will have to do small partial water changes until your aquarium cycle's. Do you have any friends that could give you a little gravel from their aquarium. Also products like Seachem Stability will help with the cycling process.