Others have asked the needed questions so I'll just go with the Panda Garras. I have 4 of the beasties in my tank and they are awesome, very active, and friendly fish. I can't reach in my tank without a couple attaching to my hand. Average mature size is ~3 inches.
They are voracious algae and bio film eaters but also need protein. They will clean algae off a plant leaf without hurting the leaf. As to protein I give mostly freeze dried tubifex worms and Hikari Carnivore Pellets but not at the same time. I feed a couple of days then skip a day on average. The Tubifex worms work quite well as I press against the glass and the Pandas tear it up then my cichlids eat up the floating stuff. They are also very hardy fish.
Reportedly they do fine solo but it is best to have at least 2, 3-4 seems to be best. While they are very peaceful the DO like to play and, if there is only 1 it will likely try to play with another fish which the other fish just might mot be pleased about.
You should also have a tight fitting tank hood as these critters can literally climb glass. This really does not seem to be much of a real issue as long as the water conditions are proper.
Water temperature: 22 C to 27 C or 72 F to 81 F.
PH: 6.5-7.5 in an aquarium. In the wild they are tighter on this.
Hardness: 36-215 PPM.
Basically they can thrive in just about anything as long as it is clean.
Oh, water flow... The filtration should push a average of 10 times the tank's volume per hour. My built in sponge filtration pushes ~5 water cycles per hour and my dual under gravel filtration pushes more.
You would want highly oxygenated water so bubbles and lots of plants are a good thing. They will also play a bit in bubbles at times. They are curious fish so some sort of cave system is not a bad idea.
All in all a friendly and entertaining critter that is not hard to keep.