Vanishing fish. Wth

[Fishyzwim]

Ok so i have a 75 gallon with 1 large cave type rock, 1 medium cave rock, a skull, with river rock on top of sand substrate. The is tank mostly for baby guppies but i also had 4 glofish danios in there. Each a different color. At some point about 2 weeks ago i realized i hadn't seen the green one in a couple days. I looked. I tested the water which didn't seem off. And i moved all of the 3 pieces of decor and couldn't find. The only conclusion i could come up with was it got eaten. Then right before bed last night i noticed the pink one seemed a bit pale so i figured I'd check her out today and if she didn't look better id quarantine her. Well i couldn't find her, but sometimes she hides in the cave until feeding so i fed, no luck. So i again moved everything. Couldn't find. Had two other people look while i moved. Couldn't find. And with what is in the tank there is no way she got eaten, WTH. Can they bury themselves in river rock? Any ideas?

P.s. it is a covered tank that is filled to about 3 inches from the top, with complete walk around area. They didn't jump out either lol

P.s.s. no snails, the filter intake has a sponge over it. Checked the whole thing.

 

[AdoraBelle Dearheart]

Have you checked the filter?
Sometimes fish hide so well, I could swear they pop into another dimension for a while before popping back. But if they don't pop back, chances are they jumped out, got sucked into a filter, or died and were eaten I'm afraid.

 

[Rocky998]

They may have died and then been eaten by snails if you have snails... You just might.

 

[Colin_T]

If the fish looked pale, it might have a disease and die during the night. Then it could get sucked into the filter or eaten by things in the tank.

Post some pictures of the remaining fish and the entire tank and it might provide more information.