Yes, water SOURCE condition/quality, not water-keeping quality.
Good. Fair enough. Neutral is literally 10 times better than pH of 8.0 and ~50 times better than 8.5.
Right. That is the only apurensis I know of too.
Funny, how our experiences differ. My 3 Cephalosilurus were sweethearts (except to each other) but they lived in a 4000 gal 40'x6'x3' pond. Can see them here on page 5: http://www.planetcatfish.com/forum/viewtopic.php?f=25&t=29488&hilit=+pet+catfish&start=80
Thanks again for augmenting my replies.
I wasn't trying to augment your replies just stating my experiences, but if your thank you is sincere than your welcome.
As far as Apurensis I've only had experience keeping one so I'm no expert. I'm more familiar with Gulpers but again no expert. I just assumed since my Apu's demeanor fit the way they where described in that mini article on planet catfish http://www.planetcatfish.com/shanesworld/shanesworld.php?article_id=220 most Apu's where like that. Still I'm well aware of differences between articles and actual experiences. So I totally know where your coming from as far as keepers and different experiences. For instance Armatus have a rep. for being hard to maintain and hard to comm. yet I've managed to do it on many occasions with unlikely tankmates(Siniperca Scherzeri, Shortnose Gar, Trachycorystes Trachycorystes, Florida Gar, Hoplias Curupira and various Vieja/Paraneetroplus all at the same time with absolutely no incident).
I'm guessing that's your thread then on planetcatfish, which means you got your Apu's from SA just like I got mine, pretty cool. I've only seen them for sale at SA, River Wonders(when they where still around) and at Tangled Up In Cichlids and at TUIC that wasn't too long ago. Apu's are one of my fave cats along with Gulpers and Trachycorystes.