Off the top of my head, I've got 30 different species in the 180:
N. venustus, F. rostratus, Aulonocara x 5, P. taeniolatus, D. strigatus, S. spylostichtus, B. spectabillis, L. fulleborni, M. autarus, P. lombardoi, C. caeruleus, A. chrystii, T. nigreventor, C. mloto, M. erichnotaenia, L. acuticeps, C. borleyi, S. fryeri, M. lateristriga, O. hererodon, P. milomo, T. placadon, C. moori, Pseudotropheus ?, S. angelicus, ancistrus
I probably have about that many in the community growout 150.
The 75 has 4. 12' rack in the fish room has 24 species. Triple stacked 40s have another 10. 10g rack has 4 species (not already counted).
Upstairs, there's 4 in the 20, 6 in the 30 and maybe 10 in the hodgepodge that is the 45 planted.
So with a guess on the 150 gal, that's 122 species... but probably over half of those are single specimens. I'm sure I probably missed some or double counted others though.
Yeah, I think I may have a problem.