CrabbyLover77 wrote: ↑Mon Aug 26, 2019 9:34 pm
My crab Beau has always been in a large plastic terrarium with a tight fitting lid, so I didn't think about it with the screen top. I wouldn't want to wake up one morning with little crabby eyes staring at me in bed lol.
There are two issues:
a) They not only push open screen tops, they push/slide open anything they can grab and that's not too heavy for them. I never used a screen top, but a sturdy plastic foil (like a "plastic glass", some 3 mm thick and hard on a terrarium of almost 1 meter length) on top and they pushed it open as long they were able to reach it.
b) A screen top won't hold the humidity. A quick fix is saran plastic wrap, a more durable one is getting sturdy plastic foil (some picture frames have that instead of a real glass) and use that. I, for example, bought such a picture frame and modified it for a lid. In your case, as you have a lid (but not a good one, as it's a screen top), you can put or even glue the thick plastic foil on top of the screen.
(EDIT: I saw you're using some plastic bags. If that holds the humidity, and you're fine with how it looks, that's fine. The only remaining issue is that they will really open the lid when something is that close to the lid and even hanging out from the tank! Mine would be out within hours for sure.)
I also had such a net/mat and I tried a few things to secure it to the tank.
a) Some thin wires, but they climbed them hanging from the wires like a sloth. With wires suspended from the upper tank frame, they came close to the lid and tried to explore a bit more than I trusted them... e.g. again made attempts to open the lid.
b) Suction cups. I got strong ones, but they were not holding the weight of multiple crabs on the net, and some crabs even tried to force them off the glass. After reinstalling them several times, I gave up.
c) Fixing the net to some branches, or even making poles from wood (just like a traditional hammock). Works well.