Brackish nano fish

I know bumble bee gobies are small but I'm not sure on stocking or what minimum tank size is, maybe someone will know. Maybe one or two would work though... I think they get up to 3 cm
 
BBG are great, so are endlers and guppies, for min. tank size i'd say a 1g for a single BBG(they can be territorial) a 1g for a trio of male endlers and a 2.5g for a pair of male guppies. you won't have enough room for them in a 5.5g however because those crabs are going to need a pretty significant land area(preferably sand) which won't leave a lot of water for fish.
 
endlers and guppies aren't brackish. . . .
 
5.5 is pretty small. iv never tried brackish but i know id want a mudskipper in ther
Mudskippers do not fit in a 5g.

trio of male endlers and a 2.5g for a pair of male guppies Danyal? i think that would be akward. total gonopodium fest
Wata said it before that neither are brackish water.;)

so would one goby work?i have a fake plant that the crabs love sitting on all day so they should be fine with that.I know they like sand but i haven't had sand with them as i would need at least a 10 gallon to get started with it
If I were you, upgrade the tank and you can consider some BBG.
 
guppies and endlers are like mollies, they do exceptionally well in BW. for a while i had 3 male endlers and a pair of females in my 10g BW at 1.012, then my knight goby ate the males, and the females didn't have any male babies(in fact all the babies got eaten) i've also kept about a dozen fancy guppies anywhere betwen 1.008 and 1.016 but invariably the males got eaten by my knight goby after a few months or jumped out while he was chasing them, i believe the longest lasting one was a little under a year. in a 5.5g a pair of BBGs should do fine as long as there is enough deco, however i just thought of something, the crabs might be a little too tempted by a motionless goby.
 
You shouldn't add any fish, as there isn't going to be much space, given both it's size and that it's set up for crabs.
 
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