Can I use a Acrylic lid on my Chamber with Cactus juice or do I need to get a glass one?

Acrylic can indeed be used for a lid IF it is sufficiently thick enough.  Cactus Juice, in direct contact with the acrylic for extended periods, can case a slimy film to build up on the acrylic but you lid should not be in direct contact to begin with.  Some chamber manufacturers claim that Cactus Juice will cause the lid to crack due to "fumes" but they do not understand the chemistry of Cactus Juice.  There are no "fumes" from Cactus Juice, even under full vacuum.  Most acrylic lid failures are caused by insufficient thickness of the acrylic.