Disappearing fish

[lakia]

Hi
I had 4 yoyo loaches that had been doing great for the past 3 months with no issues.
Anyway I was just generally studying my fish yesterday and noticed only 2 yoyos in the tank so I starting looking through the tank and found one dead in one of my small boat ornaments.
The other one I have found no sign of not even a body nothing.
Today I have done a water change and no sign of the mssing loach I even syphoned out the gravel so no chance it was buried in the gravel as no sign of it.
Anyway got my tank up and running again after the water change and the two remaining yoyos seemed okay.
Tonight I just happend to check on my fish again and can only see one yoyo loach in the tank.
What on earth is going on I have checked inside the ornaments but nothing.
Any suggestions.

When was the last time you saw it? It doesn't take long for a fish corpse to be eaten by tankmates.

Or it may have jumped out, are there any gaps it could have got through?

If the other fish did eat the dead one then they may have picked up whatever it died from. If the water results are all fine and there are no visible symptoms then it's hard to say what it is, could be some kind of bacterial infection.

we lost one of our loaches for 2 days!!!....I found him in an ornament...he had gone in and couldn't reverse back out...it took some delicate (shaking and tapping) to get him freed...

Check ornaments again...I could only see a tiny bit of tail and could easily have missed it

Have you checked inside the filter? One of my yoyos is absolutely bonkers and he constantly tried getting into the filter outlet of the external filter. He literally stuck his face and half the body in. I had to cover it up as he could have gotten fully in and he would have been shredded to pieces by the impeller in the filter. Now that it is covered, he still hasn't given up. Every evening he tries to remove the cover, thankfully it's secure. But yes, they are bonkers and would do silly things like this.