Oh yeah you guessed right they are zebra danios. And yeah you’re right I could swap out the gravel with sand. Idk why that didn’t occur to me before lol
Woo hoo! That gives us quite a few options then
Your Zebra Danios will like decent flow in the tank and slightly lower than average temperature, so that could be a good starting point. Small fish like the Zebras might limit you in terms of big fish as you dont want them to get eaten, as a start you could look to double your school of Zebras to get upto 30 which would look incredible. If you can switch to a sand substrate and make sure the tank is well scaped so you do get some lower flow areas - eg get your wood and rocks up into the top third of the tank and some dense planting with things like Amazon Swords and Vallis as some easy examples.
I'd go for fish from a similar region (broad strokes) to your Danios, so looking at fish from South East Asia and maybe some from the Congo River Basin. You could look at doing a nice school of Loaches, you could go for something bigish like Skunks which are cool, or Botia Kubutai but I'd go for a bigger group of Dwarf Chain Loaches, a really nice fish, really social and complement your Zebra Danios, a big group of 12 would be awesome! A big school of an African Tetra like Congo Tetras or African Red Eye Tetras, again 10-12 of these would be great. Some African Three Lined Catfish would be a nice addition too Pareutropius Debauwi - again 8 to 10 of them.
I'm wondering about the 'centre piece fish' and wondering if you need one with this tank if you like the idea of loads of shoaling fish. A few I was considering were some kind of riverine African cichlid like a Kribensis or Nanochromis. I've heard recently of a Jewel Cichlid called a Turkana Jewel which is stunning and meant to be comparatively peaceful compared to regular Jewels (which would be too aggressive for this tank) but I've not kept them so cant say confidently.
An other option could be some kind of Gourami but would depend on the flow you wanted to achieve for the Danios and if you were able to create natural breakers with hardscape etc? But I think a big tank built up of shoaling fish would look incredible
Wills