Interesting - are you using aquasoil? Whatever you have looks a bit more pink than AS but I thought it may be your bulbs.
So I guess your GH is around 2 Degrees... Maybe I am not sure.
Very interesting water parameters, I wonder why they are doing so well for you, seems they shouldn't breed in such low pH but I wonder if the pH drop from co2 doesn't really count.
I guess I shouldn't have any problems breeding them in my high tech tank as well as my poop box (nasty shrimp tank)
You should put some Sundadanio Axelrodi in there, they'd love those conditions provided the co2 isn't too extreme.
But Cherry Barbs would look really nice too.
I have pink bulbs up front and blues in the middle and rear.
pH movement from tannins and CO2 do not matter. Shrimp zealotry also can cause assumptions that may not be valid and are more based on breeding production without plants etc. Same with plant zealotry
No barbs will go into this tank.
Danio would be nice........
I'm still undecided as to the fish that will be placed in here, I still need to remove the rest of the rainbows, I think there's about 12-15 left.
The Double trunk elelphant nose and the all the shrimp, Gold nuggets, otto cats will stay put.
I like Gold brass tetras but as they age, they lose that nice metallic coloration, school behavior is awesome though.