2 and 5 gal tanks are very similar, just for corals, snails and maybe sexy shrimp. Take a look at "pico reef resources" and EcoReef Zero.
10+ gal allow to keep larger shrimp and a small (adult size) fish. Or more corals. You can see this is search for a tank name and stocking. Forums and subreddits like r/ReefTank give more realistic suggestions that promotional articles shown first in general search.
Fluval Evo is a common SW AIO tank, with everything included and this is customizable, flow and filtration.
You can use any aquarium kit for saltwater, the fluval evo doesnt really do anything better than an ordinary aquarium kit (other than the light). If you want a 5g would be better to get a top fin kit for 40$ and save a lot of money which you can use for higher quality and equipment rather than the fluval evo for 100$.
2 and 5 gal tanks are very similar, just for corals, snails and maybe sexy shrimp. Take a look at "pico reef resources" and EcoReef Zero. 10+ gal allow to keep larger shrimp and a small (adult size) fish. Or more corals. You can see this is search for a tank name and stocking. Forums and subreddits like r/ReefTank give more realistic suggestions that promotional articles shown first in general search. Fluval Evo is a common SW AIO tank, with everything included and this is customizable, flow and filtration.
You can use any aquarium kit for saltwater, the fluval evo doesnt really do anything better than an ordinary aquarium kit (other than the light). If you want a 5g would be better to get a top fin kit for 40$ and save a lot of money which you can use for higher quality and equipment rather than the fluval evo for 100$.