Pictus and white line pim cats. This may be different in larger groups but mine spazed out often despite their some-what small size. I had to move them out of the 75g when I got the panaque and put them in a 29g. Though the 29g looks large enough...especially for the pictus...they would spaz out and jet around the tank. I would never keep them in a small tank again.
You'd think he would haul ass to the other end and stop and wait 'till I'm done, but oh no!, he has to go round and round a few times. Getting a bit of a flat spot on his nose. 