Head Scratcher Deaths...

[xXInkedPhoenixX]

My Flex9 is having issues. 18th found a deceased Oto. Today (20th) deceased Ember. Nobody looks or acts sick. Examination of both Oto and Ember gives me no clues. The Oto still looked like one, no unusual redness, spots fin issues appeared to have been eating fine, etc. The Ember (who was seen alive just the day before during roll call looking fine) Found deceased, turned from the translucent orange to mostly white but otherwise looked ok- had to have died sometime between last night and the time I found them. 

Water parameters just tested Thursday: Temp 78.9, pH 7.6, Ammonia/Nitrite 0, Nitrate 20. 

Stocking 2 Male Endlers, 1 Hillstream, 1 Oto, 5 Embers, 3 Nerites. 

Recent changes: 

Guppy grass added (but also added to another smaller tank no issues there. 

1 Endler recently ill, was removed and QT passed of unknown illness but had visible redness around lips and in the end gill area. Treated with Furan2 no change, started Kanaplex- but deceased before end of treatment. Nobody shows these visible signs. 

Did notice that flow was an issue in the 3rd back chamber where the pump is but that couldn't have been happening for very long as I would have noticed it yesterday during routine maintenance AND the Oto died before that was noticed. 

 

SO, not having a Scooby Doo about what is going on I threw a dose of Furan2 and Kanaplex in. What do you think? Any ideas? 

Also anyone know if my Nerites should be pulled for sure...I would normally anyway but they are out of reach at the moment. 

[Colu]

Unexplained are usually caused by a bacterial infection as your endler that died had  had symptoms of a bacterial infection I would treat the tank with kanaplex and furan2 together as it's an on going issue some strains of Columnaris can kill your fish without exhibiting any symptoms

[xXInkedPhoenixX]

Well, @Colu thankfully that was my instinct- I'm assumimg bacterial. I did both right after I posted (well, added Kanaplex). I also was able to pull all 3 snails and put them in comfortable quarantine. So it made me more comfortable to double up.