siamese algae eater

[DN530]

I just recenty bought a full size siamese algae eater (Crossocheilus siamensis) to help clean up some hair algae on my plants. it does an AWESOME job. the only thing is that 4 of my fish have died since i've put it in the tank a week ago. i am positive that it is not a flying fox or a false siamensis. all of the articles i read state that a the siamese algae eater is not agressive unlike the flying fox and the false siamensis. any explanation on why 4 fish are dead? hes in a 29g with 9 cardinals, 3 cories, 2 gold tetras 4 pristillas, an otocinclus and a guppy. now the guppy is dead, along with 1 cory, 1 gold tetra, and 1 cardinal. all the deaths have been on different days. is this fish agressive, or did it bring some sort of parasite or illness to my tank? HELP!!!

 

[The-Wolf]

what are your water parameters like?

 

[DN530]

ph 6.8, nitrates 0, ammonia 0... not sure about water hardness