woud a diamond tetra eat a dwarf rainbow?

[zeebo]

hi. just added 3 female dwarf rainbows to my main tank yesterday. Prior to adding them , I have 1 male and 3 other rainbows. This morning I found one gutted and floating , and another female completely missing.

Here's the stats:
54g
2 Aqua Clear 70 filters
2 air stones
gravel substrate
wood, caves and silk plants

fish : 1 farlowella
4 diamond tetra
11 juvinile harlequin raspbora - 4 added last week,very small
4 dwarf rainbows ,3 female,1 male and the surviving 1 female

took everything out of tank to look for the other female's remains. Nothing found. Could the diamond tetra have done this and why as they have been living with the other 4 rainbows for a few months and never a loss.

any insight here appreciated . thanks

 

[Lornek8]

Were the rainbows quarantined? Are they kept in simple tap water at the store? Could be, as with most heavily captive-produced aquarium fish that they are simply weak fish. Once a fish dies it becomes open-season for all others to pick at and although the diamonds may not have killed the rainbows, they could have added to aparent damage. I'd check very well around the outside of the tank just in case the missing one jumped.

 

[zeebo]

stupid and risky , no didnt put them in the q-tank as i put some others in there and did not want an amonia spike--next time won't buy so many fish at same time so the new ones can only go in the q-tank. Well I will get the flashlight out and look around , with the corner tank being deep it is hard to see around it without a good light. Thanks . I know it dosen't matter what the store says, even if they are reputable as I find this store to be, said no new fish were added to that tank in over a month, but i know better and shpuld have purchased onlly what i could safely add to the q-ank. My stupidity for being like a kid in a candy store , because the store is so far and i dont get there often enough, now wating game to make sure nothing bad came in with them, Thnals Lornke for the response.