Snail nuisance

[Jmlorfam]

I have a minor nuisance issue. My snails are making their way into my overflow box and into the overflow siphon tube. Does anyone know of a easy DIY fix for this? I was considering some type of box cover but don't want to reduce the functionality of the overflow box. Any suggestions are welcome.
Thank you in advance.

 

[mr_X]

you can go to the crafts store and get some netting or eggcrate (light diffusing material) from home depot and place it on top.