Is this "too much" fish for a fluval edge...

Sorry...they are beautiful fish. I have 20 of them!! :)

Now you're just showing off... ;)

I will look into both of the fish you recommended. I do, however also like black neon tetras. I know they are on the biggish side, but they are much smaller than the diamonds. Now I'm off to look up the raspora espi and the gold ring danios
 
Any danio will be far too active for that sort of setup. I too would suggest you return the diamond tetras, and go even smaller than espeis. You could have a nice school of microrasbora in there, without the tank looking cramped, and without the fish feeling cramped either. The crystal red shrimp would probably have issues with the water quality in such a small tank, especially given the fact that they're gonna be sharing the tank with fish. Amano shrimp are not quite as pretty, but much hardier overall.
 
or you could fit 10 or so of something like the pheonix rasbora or chilli rasbora. They are both very vibrant and look great.

Another alternative would be dario dario,also very pretty.

I agree that there is just no way diamond tetras will work. I have 9 in a 36g and wish they had more room.
 
I sometimes feel my diamonds are cramped in my 46 gal bowfront. They are just such avid swimmers, and they are CONSTANTLY on the move. Kind of remind me of danios in that aspect. They go speeding around in there like they're off to the races. I'd be hesitant to put them into anything that small... They are pretty good sized. My adult males are around 3" long (including tails), and the females are closer to 2" in length. I have at least one juvie that is about 1", but is steadily growing. Not sure which of them paired off to lay eggs, but they only did it once (or the fry only survived once). Anyhow, I'd be leery about the diamonds in there. JMO of course.
 
Yea, I'll give up the diamonds... probably go for a school of black tetras and cherry shrimp instead of crystal.
 
Black neon tetras are a better choice than the diamonds, but would still be really cramped in there IMO. Assuming pet store markups, you could probably buy everything you want for that tank right here on AC, and even factoring in shipping, break even with LFS prices. You may even save some money, considering how much some of the stuff you can find cheaply on the forums would cost in a LFS.

These are the boraras brigittae that MsJinkzd was talking about. They're easy to keep and feed, and would be a much better fit, size wise for your tank, not to mention their gorgeous looks.

boraras_brigittae_m.jpg
 
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