Need some ideas from some of you guys.I have a few rasboras,regular and black harlequins,and scissortails.The scissortails and reg.harlequins have all been fine,yet I have found that every one of the black ones are having issues.The pectoral fins turn white,they cant move them and then under it turns red.They die shortly after this.

As for tank mates theres the two regular and three scissortails and then the two betta Pi.55 gallon tank,temp about 79.No one else is affected just the little black ones.Filter has been through the nitrogen cycle,and of course the tank is planted.

Any thoughts on what this could be?All the black ones have been moved to be treated with heat and blackwater extract.

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http://bountifulbettas.blogspot.com/

"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

I'm an absolute pain in the posterior wild-type purist, so feel free to take what I say with a grain of salt - BUT, while I haven't seen black rasboras around here much, I assume it's a breeder form. Cultivars do generally tend to be more fragile than natural forms. They aren't the result of hybridization but very narrow inbreeding for a goal - and such fish will often be struck down by pathogens that don't even affect tankmates.

If you are making a genetic selection for black, what else are you selecting as you narrow down the field, cross parents and offspring, and do all the things necessary to fix a strain? As you breed in colors and forms you want, you can accidentally breed out immunity, strength and vigor. We see it big time with dwarf gouramis, blue rams, long-finned livebearers and other man-made forms, and maybe you are seeing something bacterial take down your rasboras selectively?

it certainly sounds bacterial.

Hm,does make sense.One thing I love about my wilds they are tough guys.Any clue what to treat with or is it even worth trying?Because I dont know what meds will effect the Pi,I would rather not add chemicals to the tank,save for natural things.

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"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

can you do a dip insted of treating the whole tank?

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"Being ignorant is not so much a Shame, as being unwilling to learn".-- Benjamin Franklin

They are just so hard to catch lol.I have been removing the infected to the 20 long,where I have salt,tannins and higher heat.So far the ones ive placed in there have been doing a little better.

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"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

that's good. I hope you can cure the little guys!

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"Being ignorant is not so much a Shame, as being unwilling to learn".-- Benjamin Franklin

You stealing my thunder?

I used to hang out on Guppies.com a lot and there was one individual that was the queen of curing weird stuff. She would always mix a couple of different meds (appropriate to the issue) and dip the fish for usually less than a minute and then put the fish back into the tank, or into some cheap plastic containers to isolate them. There were not QT tanks with filters, heaters, etc.. Some were even picher-type containers that you would normally keep kool-aide or ice tea in. She was the only one that I had heard of that actually had success at curing columnaris. You can google dips and even believe there is some stuff on youtube.

That's what I was thinking when I saw the post, but you said it already.
It sounds a bit like problems not very hardy fish can start having when kept too far out of their natural PH or GH range, just a thought.

The PH range is right up their alley at 6.0.These are hybrid harlequins,and the two normal harleys are fine.

I have noticed after the pectorals turn white they get red at the base of it,like something i irritating them.

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http://bountifulbettas.blogspot.com/

"Come to the dark side....we have cookies...and filters/heaters/and water changes!"

I've seen exactly what you describe, and only on blackwater fish. I've seen it on fish at importers', soon after arrival, and after shipping stress. I've had people whose expertise I respect 100% nod, and say it was a bacterial disease.

But no one I know of has taken the fish, put them in a lab, and properly diagnosed the pathogen. That's a problem in this hobby - we don't have state of the art fish-veterinary labs in our basements!
So, is it bacterial? Most likely. Is it gram positive or gram negative bacteria? Who knows? So you can't throw antibiotics at it, because you have no clue what will work... I don't, you don't...

It will follow the pattern of a bacterial infection. It's internal and it shows externally at a late stage (I think) so salt is actually bad - a Rasbora isn't adapted to deal with salt. Melafix is almost homeopathic in its concentrations - the active med works, but not in such a low dosage. So that won't help. I'd catch them all, amid much cursing and bad language cause they are fast if they aren't at death's door, and isolate them in clean, tannin stained water, maybe with those wonderful Betta/almond leaves. Do a voodoo dance and watch what happens, as hard as that is. Keep it clean and see if they can fight it off with tlc.

I know I sound fatalistic, but we know so little about these things, and sometimes we just have to expect losses and be glad if we are luckier than that.

Well let us know if the dance works, lol. It will be interesting to know the results.