Hoover Performa 1100?

My mother in law gave me her Performa 1100, which i have no problems with but.... Which part does the fabric softner go into? There are 2 long hole, if using powder I use the middle hole, (I usually use tablets tho) and then there is a longer slot, split into 2 parts, would I put the softner into the smallest or longest of the slots, (Hope you understand me!!) the smallest part has a pic of a triangle next to it and the longer has a pic of a flower. Im not even sure if I should use either of these for softner as I did a wash this morning, put softner into the smallest part and it is still there, although diluted with water.