3 Neons Stuck Behind 3D Background

[Sharpy14]

Recently bought a Rio 180 off eBay and it came with a 3d resin juwel background fitted, but overnight 3 of my 17 neons have got through a fin passage on the end of the tank, I can sorta settle net behind the crack but unsure what to do. Pics after,

 

[saltynay]

2 options

1. Remove the background.
2.Tap on the glass working your way towards the fish they will panic and hopefully find the way out.
3. Wait for them to figure it out on their own

Buy some aquarium safe silicone to plug up the gap or fill it with sponge once they are out

 

[Sharpy14]

ok but the background is professionally fitted and filter is built into it, can't remove it

 

[N0body Of The Goat]

Lure them out with some defrosted bloodworm placed at the end of the opening, perhaps?