Yea I cleaned out the entire gravel today and did a 50% water change. I also put in a second cycled filter system to clean up the tank, I feel the one that came with is not really cutting it.. Fluval SPEC Freshwater Aquarium Kit, Aquarium with LED Lighting and 3-Stage Filtration https://www.amazon.com/dp/B009S8NO26/ref=cm_sw_r_cp_api_glt_fabc_3M43YQVW6KXPPFBZ8XNX?_encoding=UTF8&psc=1
It's a sponge filter, built in with the tank (it's this tank, btw)
I did a water change just yesterday, too - Would that change the results? (and should I do one again so soon, even if it might stress out my fish and make him sicker?)
I am using the stock lighting for the Fluval Spec 3. And how would you cut it? Just with scissors?
It depends. I suggest checking out the Walstad method if you would be interested in a shrimp tank. Shrimp can do well in a jar or bowl with plants, no filter, no light, presuming you have the bowl in a spot with enough light for the plants. Some plants would do fine with just regular office lighting, but others are picky.
Fish usually require a filter because they're dirty poop machines and benefit from the current. Betta fish like calm water and can live in a bowl (that's why you see them in those depressing cups at pet stores) without filtration, too. They require a lot more water changes because again, poop machine and nothing to stir up oxygen into water.
/r/shrimptank and /r/aquariums are good resources if you're looking to get set up. If you want to go bigger, I have this tank for my desk. It's silent and acts as a great lamp and I've never once did a complete water change and I've had it over a year (just topping off tank when it evaporates).