Spate Of Deaths

[Dutsey]

I have had a spate of deaths in the last couple of weeks.

I have lost my male and baby guppy (baby was 3 months old) , all of my oto's, female GBR and now my bn plec.

I am no sure why.

Done a test and they are fine.

Nitrates - 20ppm
Nitrites - 0ppm
Ammonia - 0ppm
PH - 7.6

All my other fish appear to be ok. I am miffed and confused as why this is happening. It is driving me potty.

 

[Fishy friend2]

Put up some pics and we could help even more

How big is the tank how often do you do water changes when was the last time you added some thing to the tank did they have torn fins or white dots on them