I have 5 garras in my 55G. They were sold to me as Khasi Garra (Indian red-tail) but I'm not sure if they are. For one, they are grayish silver with no hint of red anywhere and they do have a small blue spot behind their gills. Most of the pics on the web were not clear enough so it could either be Khasi Garra or blue spotted Garra.
Anyway, these are very peaceful algae eaters. They love to chase each other and can move very fast so they can stress slower moving fish. They go crazy at feeding time competing with other fish for food. The five in my tank are becoming a little more territorial, but only chase each other, not other fish. They also leave my RCS and Amanos alone. I might have to reduce the population down to three and transfer two to another tank. In terms of algae control, they do a fair job. They won't eat BBA, nibble on everything else, and love brown algae. They are not the Dr. fish (Garra ruffa) but will come up and playfully suck on your hand and arm when you do maintenance in the tank. Once in a while, I'll scoop one out of the water then let it back in. In a minute or two, it'll be right back playing with my hand again.
If you want a slower moving Garra that won't scare other fish, go with the Panda Garra. $12 is about the right price for those. I got my Garras for $2.50 each at a LFS, but they haven't carried them for about 8 months now.