Hi, welcome to the forum
Its up to you what fish you like but generally its best to get a group of fish for the bottom, a group of middle level swimmers and a group of top level swimmers. Since the tank is fairly small, stick to smaller fish like tetras and rasboras for the mid leve swimmers (these all like to be in groups of 6+ of the same variety) my favourites are cardinal tetras and rummy nose tetras and harlequin rasboras.
For the bottom of the tank shrimps (avoid the ones with claws as they will catch and eat fish) fan shrimp are nice and amano shrimp or cherry shrimp. Corydoras (get at least 3 of the same variety)or khuli loaches 3+
For the top, hatchet fish (6+) or dwarf or honey gourami (1 male to 2 or more females or a group of females or a male on his own).
For an algae eater otocinclus are great and only grow 2 inches (need to be in groupd of 3+) Or bristlenose plecs are nice and only grow 6 inches. There is a pinned topic on plecs which stay small. Avoid sucking loaches also sold as chinese algae eaters as they get aggressive when mature at 10 inches, also avoid common and sailfin plecs as they can grow 2 feet long.
There are lots of combinations but work out how many gallons the tank holds then aim to have no more than an inch of adult size fish per gallon, (this guide only applies to small slim bodied tropicals under 3 inches) Research any fish you plan to buy and get the max size don't be conned by the shop telling you that things like bala sharks and clown loaches will be fine as both these fish grow 12 inches long and need to be in groups in much larger tanks.
Get together a list of fish you like and post it on here to see what people suggest.
Emma
