Guinea pigs - is this cage safe?

[Samoyedy]

I've just been given a new hutch which has a normal hutch space on top and a ramp leading to a run on the bottom, there is no door to close the run. Is this safe? I'm worried about rats getting in because of their food? Is there anything else I should be thinking about? Do I need to block the door off to leave them in there? Please help!

Can you link it?
Is the door leading from the upper to lower levels.
Providing the whole run is enclosed, you could use another layer or two of finer chicken wire to stop rats/mice.
If the run itself is open, I'd be more worried about cats and foxes .
And maybe peg it down with tent pegs to keep it secure on grass.

There's a permantly open door (no flap etc) leading down from the hutch part to the fully enclosed run. I'm just really worried about rats won't they dig under to try and get in to the food in the top hutch?

Also, what about the pigs, what if they go down to the grass in the night and freeze to death! Will they know that down there is cold and up in the hutch with all the hay is warm??

This would be fine in the daytime, and they'd probably love it. But I wouldn't if they are out there all night by themselves with the door to the outside open. I'd be worried like you.

Come to think of it, it probably wouldn't be the greatest idea to give them unlimited access to grass, as they can get bloat (excess gas from eating too much grass and green veggies, something they can develop as they get older). Guinea pigs cant pass gas like we can, and bloat can be fatal.

Could you bring them in overnight? (You can get indoor gp cages, they look like giant hamster cages, depends how many gps you have I suppose). But I presume you don't want to spend money on another cage.

Or could you just engineer a door to block off the ramp at night?