Kuhli Identification?

[OrigamiOokami]

I bought 6 Kuhli loaches about three or four weeks ago, and when I received them I noticed all their bellies were a very deep red. I have a different tank with several Kuhli, and none of them have red bellies, but since it was all 6 of the new loaches, I thought it might just be a species variance.

The reason I bring it up is because I have noticed from the very beginning that a couple of the new loaches swim erratically up and down the tank (nearly 24/7), and in a more agitated and speedy manner than my other tank’s Kuhlis have ever done—and now it seems that all six of the new Kuhli loaches have begun swimming in the same frantic manner.

I’m just wondering if this is normal behavior or not—or if it’s maybe a subspecies-specific behavior? Like maybe they have more energy than my other tank’s species…? They're swimming so frantically that it's hard to get an un-blurred photo of them. But their red bellies look sort of like a sunburn, with a deeper red section where (I'm guessing) their stomach organ is.

Oh, and my parameters are (15 gal moderately planted tank), Amm/Ni: 0, Nitrate: 5, pH: 7.4, gH: 8, kH: 3, temp 78. Seemingly no other sick fish, and no aggressive tank mates or sharp gravel.

Thanks!

[Diana]

Are they a striped pattern? There are more than one species with stripes. Some include some spots among the stripes, some have stripes just going about half way around their body, others have more complete stripes.

Just how red are they? I hope they are not sick or infested with internal parasites. Might be a good idea to use a worming medicine.

The up and down swimming seems to vary, but I do not know if it is species related. I have had some Kuhlies do this a lot, some almost never.