I don't think so I think correct me somebody that @ 4ft high you need 3" or thinker.... I might be wrong but I think it needs to be thicker and if money isn't a option I would pay for thicker anyway.....
2" thick is enough when yo support the acrylic on all sides. your tank will look amazing when done, is it going im your basement? 1.5 would be enough... but i personly would go with 2", its impasable to find 3", you have to get them to make it.