So I hadn't seen my mandarin in a few days. My wife was under the tank and caught a glimpse of what she thought was the mandarin in the sump. She then shut off the skimmer and lift pump and sure enough the mandarin was in the sump. Then a little flash of yellow caught her eye in the body of the skimmer.
The clown goby disappeared over a month ago and has apparently been living inside a Octopus Cone skimmer for that time. No idea how he got past the impeller but he is happy, fat and back in the display tank.
Further proof microbubbles will not kill fish ;D.
I can't imagine getting past the impeller either... maybe he went in the outflow?
Same thing happen to me several years ago with my Yellow clown goby, was cleaning the intake strainer and came back to reattach it and while I was gone. The goby must have swam into the open intake of the skimmer. I notice he was missing for a few days, he was not perching on his rock. Went to clean the skimmer overflow cup and caught a glimps of something in the bubbles of the skimmer. Quickly shut of the skimmer and guest who was swirling for 3 days in my skimmer. He manage to swim into the skimmer while the blades were running and didnt get cut up. Unfortunately I figure the carpet anemone became his dimise, he went awol one day.
Glad to see you found your goby.