i really like the look of the dats and have heard they do well with the gars, so my question is, in a 180 gallon tank with 2 florida gar, 2 albino senegalus and 1 ornate bichir, how many and what kind of dats would i be able to put in?
You can put any of all the species of datnoids in there. But good luck finding a ST.
Dats are a S....L....O....W.....growing fish so you might want to pick out a size where he won't eat your other stock, along with him not being able to get eaten by your other stock if they grow a little more than him. I say 1 or a group from 3-5 will do good in a 180 gallon. Lets see and wait for those dat-freaks to tune in though.
At 2" only, I'm sure his tankmates will outgrow him and eat him in no time EVEN if they were to start at the same size. IMO it's better to grow dats on their own until they hit a size where they are too big to get eaten or eat others (I say around 5"-8"). Although the senegalus poses no threat to the dat in the long run as they only grow to around 11"ish. The only thing that I will worry about is the gars, and the ornate as they can get 2'+.