I need your help here, because I never used mesh for my atomizers, and therefore I don't really know how does this material look and feel like (photos don't help much).

So I have a water pump that can't be used to suck dirty water, but that's exactly what I'm going to use it for, and to filter out sand and other fine-grain dirt, I was going to build some kind of filter, which has to be applied on the end of a soft-plastic pipe (the green ones used for watering your garden).

So what I'm asking here is if this is so tight that it can actually filter out sand, and resistant enough as to not get broken to pieces and sucked in by the pump (it's not incredibly powerful, just 0.5hp for a 18mm width tube).
I can obviously use more than 1 layer and even put some kind of sponge between the 2 layers if needed, just wondering how tight and resistant it is.

Also what is that number (400 in this case) in the mesh model? I guess it is how tight the mesh is, so the higher the tighter, or the other way around? I don't know the technical terms used for meshes so forget me about that.

Thanks in advance.