Have recently set up a driftwood and rock blackwater biotope tank for my new gold nugget and two gibbies. used aged aquarium water from other tank, still cycled for a week with two guppies, all parameters good. moved catfish in 3 days ago. they look really happy, in fact the gold nugget who did not (at least during the day) come out of the ornament the entire two weeks quarantine, came out immediately on moving to the new tank, and is the most social now.
have noticed all the catfish very occasionally swim up to the top of the tank to the surface and come down again, ?getting a gulp of air - don't know. have a good current, tank should have lots of oxygen. they then keep on sucking, is this to do with feeding?
otherwise all normal, as i said all look pretty happy. the gibbies don't do too much, but the gold nugget quite active.
i love my catfish and new natural looking tank. got the biotope idea of your website - thanks very much, great idea.