will all these together fit in a 6x2x2 tank?
Blue acara
Banded leporinus
Heros severus
clown loach
black lance catfish i realy realy like these
Synodontis Catfish
oscar

just about every fish you have listed grows to about a foot or so. even the clown loaches though slow growing will eventually get large(and they are better in schools of 5 or more) i think that when all are mature you may find yourself a little overstocked.

erm..ok lol, how many would fit in that size tank?

the size you quote is the same as mine 6x2x2. I have 2 x 10" oscars. 1x 8" parrot. 1x7" & 1x8" clown loach. maintaince is 30% water change once a week and nitrates stay well below 20% now.my tap nitrates are 10%. I am looking for a extra clown but as necromancer has said they are very slow to grow. I got mine 6yrs ago 1.5" and they are only 8" now. I may even add 2 if i find them of the right size. i think thats the best way for me to explain how many fish you could put in because as you know you could add more but the work load increases to a un manageble amount. I did at one point have 4 oscars as you probaley remamber but 2 died. The work load then was 2x30% water change a wk. This I truly would not recommend to anyone. I am very keen fish lover but it was hard work with this maintaince plan.(my clowns are still growing sloooooowlllllly)

thats great help thanx marcus