Spader
Fishaholic
i think u should return the livebearers also for something else. or maybe get more unusual livebearers. good luck! 
balas in a 40 g? LOL
THATS LIKE A HUMAN LIVING IN A CARDBOARD BOX
OR A PLECO IN A FISHBOWL
you can have tetra's and angels together..... not in all cases admittedly as the tetra's are a natural food source for angels, but if they grow up together or you get the tetra's as adults and the angels as babies then they should be fine as they won't see the tetra's as a food source, if Paul's had them in the tank for a while with none getting eaten then they probably won't get eaten!
http
/www.fishforums.net/index.php?showtopic=132656
Usually not too much damage, although I suspect he is the reason my crypt hasn't been happy lately--it doesn't appreciate him cleaning off the leaves. You'll probably have these issues with any small pleco, unless you get ottos. I had a couple of pitbull plecos (also very cute, stay at 2 inches, but mine mysteriously died
), and I believe they caused my hornwort to defoliate at one point. However, I have seen them in a display tank at a pet shop once, and it was fully planted and beautiful so they can't do THAT much damage. Like I said, it is an issue that is possible in a planted tank with plecs.