Missing fish

[Reema]

Hi, I had 12 cardinal tetras in my 20 gl tank, for about 2 month now. They were thriving and everything was fine, water parameters always good because I'm very diligent with maintenance, but since yesterday afternoon 3 of them are gone missing. Only 9 are swimming about and even at feeding time the 3 didn't show up. I'm a bit perplexed. 3 in one shot ?
My tank is heavily planted so I can't spot them if they're hiding or dead by just looking. Tomorrow is maintenance day so I'm gonna have to drain water and shift stuff around to look for them.
What could it be that 3 of them are MIA all of a sudden?

 

[earhtmother]

Any other fish in the tank? Any snails?

 

[Reema]

Any other fish in the tank? Any snails?

Yes there are other fish. 3 platties and 2 corry cats. As far as snails, 1 assassin.
Its weird. Yesterday early morning they were all there. In the late afternoon I noticed that 3 are missing. I do a head count every morning.

 

[libertybelle]

Definitely look around but you’d be honestly amazed how quickly a tank full of fish/snails can strip a dead fish...

Check your ammonia/ nitrite though, if it’s rotting one where it might cause levels to fluctuate.

Did you check around the ground/ back. I don’t think they’re known for jumping but sometimes they surprise you.

 

[Reema]

Found them trapped in the pump intake. I'm surprised because they are not small and the intake is not powerful. Weird. I'm gonna have to attach some sponge to the intake.