Mines 120L/30G. Similar dimensions and very hard London water.
Currently temporarily holding:
4M/8F Long Fin White Cloud Mountain Minnows
3M/6F Medaka
3M Guppies
2M/6F Heterandria Formosa.
until the HFs species tank silently cycles.
I can’t recommend the LFWCMMs enough. They’re gorgeous and extremely busy around the tank. Medaka are good but I’d recommend getting single colour only and not the red/white ones I’ve got for purely aesthetic reasons. Guppies are.....well.....errrh Guppies, they add a bit of variety visually.
The HFs though I love. A very small nondescript fish that because of the action in the tank from the others seem to spend most of their times in the planted back n sides. When they do come out into the open they’re not intimidated by the other bigger fish. Their appearances at the tank front seem to become events! Like a celebrity visit or a ship launch by royalty!
@emeraldking thought they’d be a bit shy and I only got em out of my preferred order because of C19 supply difficulties. Theyll hopefully have their own place by the New Year.
All the above fish don’t require a heater indoors and will be outside in their own “ponds” over the summer to hopefully make little fish.
I can’t recommend LFWCMMs and Medakas enough though their temp range limits their possible tank mates somewhat.