Danio with dropsy, do I treat the rest of the tank?

[EmmaC]

I have a danio that looks to me like it has dropsy.  I have quarantined it from the rest of the tank but now I’m really analyzing the rest of my fish to see if I see any early signs.  I have danios, gouramis and fancy guppies in the tank.  My gouramis are looking a little bloated to me (they did recently eat) but other than that everyone is acting normal from what I can see.  Should I treat the rest of the tank just to be cautious? Is there anything to do for my sick danio? I assume it is advanced dropsy because it looks like the fins are pineconing severely. I’ve never dealt with dropsy before.

Nitrate: 20

Nitrite: 0

Hardness: 0

chlorine: 0

Alkalinity: 0

PH: 6.8ish

Temp: 71 degrees

Sorry in advance for the awful photos of the danio. It’s a quick and active little fish! Thank you so much for the help!

 

[Tony s]

There may not actually be anything wrong with him. I have glow fish danios over 2 year’s old that look like that. I tried a lot of different things at first. No results. So I gave up. They’re now over 2 years old.  But I’d be checking the side scales to see about pine coning. If she looks like she has scales pointing out, then probably dropsy. 
dropsy is not really contagious, it’s usually a sign of bad water quality. And not really curable. I’ve never been able to cure it anyway 

you could start with aquarium salt. Possibly at 1 tablespoons to 5 gallons for a week. And see what happens 

[Colu]

Could be egg bound if it's a female what I would do is add epsom salts baths  1 table spoon for 2 gallons for no more than 15 minutes for for 5 days as Epsom salt acts as a muscle relaxant if in 5 days your seeing no improvement then I would do a course of kanaplex