Fish Ident please

I just picked up these 4 fish off Craigslist and need an ident. They were sold to the guy I bought them off as Port Cichlids. He did not post a pic and all research I found on Port Cichlids stated that they were compatible with my tank mates. I am just hoping they are compatible now that I have bought them. I was a little cautious once I realized they were not the same fish I researched but they seemed to school and I figured they would work. I am now debating getting rid of my Giant Danios that I bought as dithers. The new fish are about 4" long. The owner was told that they were full size.

125g with 45 g sump.

Inhabitants

6"" Rotkeil Severum
5" Chocolate Severum
8" Ghost Knife
4" Buffalo Head - yeah, yeah, I know different part of the world but I have had him for 2-3 years and he gets along fine. One of my favourite fish
5 - 3" Giant Danios - my dithers
3 Congo Tetras - had more but they "disappeared" before they became large enough to be unedible.

No time for pics today but I will try and get some tomorrow. I am in agreement that they are not cichlids but just don't have a clue what. The bottom fins on 2 of them have some red in them if that helps. They have the same type of mouth as my Buenos Aires Tetras. Oops I just realized I mislabeled my Buenos as Congos.

I was hoping that the new ones were at least South American to fit in with the majority of my other fish. I have my doubts that they are tetras just because of the size. They are close to 4" long with about a 1" depth to their body. Fast moving schooling fish.