What Would You Put In This 100L/26Gal Tank?

[Raticataticus]

I already own one of these (the larger one) and currently have 3 goldfish in it http/www.aquaone.co.uk/UFO_aquarium.php
(a temporary home for them, am getting a more suitable tank for them very soon)
 
Any suggestions for what I should put in a tank like this?
 
(I already have a tropical community tank with guppies, mollies, snails, dwarf gourami, bristlenose and will soon add cories and kuhli loaches and perhaps some cherry shrimp too.)
 
I already have a betta in a smaller tank that I could move to this one. Any betta tank mate suggestions for a tank this size? Or other suggestions for what to put in it?

 

[LyraGuppi]

What are your water parameters, Kh & Gh, Ph?

 

[AshleyNZ]

Glad to hear you're re-homing the goldfish

Bigger is always better with them!
 
I had a semi circle tank, it was 65L, and I had it planted, with sand and a feature piece of driftwood, with a few honey gourami and a big school of neon tetras. It looked AMAZING. You could even add some cories to it too, my tank was too small for bottomfeeders, unfortunately. 
 
I also have to say I would not recommend having tankmates with betta, as they can be stressed by highly active fish, and are prone to getting their long, flowing fins nipped at. Also the betta could attack the smaller fish. Personally, it would not be a gamble I would take. Other people have had success though.