Any fishkeepers here? Saltwater or freshwater

[htismaqe]

Originally Posted by Silock

Well, it does take a few minutes for it to turn green, so it looks like the prime is working.

However, it's too late for the betta. He's got dropsy, probably from the nitrites. I doubt it's from the tetras, but it's possible. I wouldn't think any infection would have gotten to the betta this quickly.

Dropsy is usually caused by Aeromonas bacteria. It's possible he had it all along and you only noticed it once it got bad enough to show external symptoms.

Nitrites wouldn't cause it but continuous exposure to ammonia and nitrites would certainly leave him VERY susceptible to Aeromonas infection.