Keeping snails out of the overflow box

I have a eshopps overflow box and I can't keep the damn snails out of it to save my life. There are five in the outter box now and often I'll see a big one cruisin around inside the utube. It's been jackin with the flow and the herbie tuning, so it needs to stop.

I've thought about either:

-Installing some kind of screen over the top of the inside skimmer box. I like the idea of egg crate cause it's stiff and could easily be set in place and removed, but the holes are too big and would easily let snails get in there. Some sort of gutter guard mesh has smaller holes, but isn't stiff and would be harder to install in place. Maybe a combo of both?

or

-Installing some kind of very small gauge screen on the intake end of the utube. But I suspect that method would easily clog and quickly reduce flow anyways.

Thoughts??

 

I would just put a lid over the box to prevent the larger snails from entering.

 

Well yeah.. I was looking for advice about what kind of material others have used. I've rulled out a solid piece of acrylic

 

You could get a small sheet of plexi from lowe's/home depot, drill 1/4" holes in it spaced about 1/2" apart and place on top of your intank OF box. This will still allow you to see into it but not let the snails in. JM2C

 

i've got a rather simple solution i used on my skimmer overflow box.






you can get those little zip loc things in lots of sizes. It 'hugs' it really well.

 

Very interesting.. and that lip prevented your snails from crawling over it? I'm very surprised how mobile these snails really are.