I bought a school of Bleeding Heart Tetra 2-3 weeks ago, and since they've been coming down with a mystery illness that comes on very rapidly, and kills them off within 24 hours of onset.
My water parameters are "fantastic" as per testing at Big Al's. 0 nitrate, 0 ammonia, etc., etc. My tank is a live planted 20 gal. long with dual HO full spectrum lighting, heated to a consistant 78°F, thoroughly aerated with two bubblers, and a Tetra Whisper EX70 HOB filter. The tank is cycled.
The illness begins as whitish bumps, which moves very fast all over the body, taking fins and tails. They gasp for breath. They become disoriented and unable to balance themselves and boom! dead.
I treated them for 7 days with Pimafix and Melafix. Did a 33% water change following it. No difference. I've lost 5-6 of them. Started out with 17. I have 2 more sick in the tank as I type this. Whatever this is, it wants to take them all.
On a side note, my three Otocinclus and 4 African Dwarf Frogs are completely unaffected by this, and all seem happy and healthy. They show no illness whatsoever.
I've attached some pics. Sorry about the poor quality. But you can see the white areas I'm talking about.
Please help! I'm not sure what it is, so I haven't treated it effectively. I've googled the heck out of this. I've badgered the guys at Big Al's (heh heh!), to no avail. Is it a form of costia? Advice needed, please and thanks.