I think the idea with the corner guards is to have an easier way to attach platforms/caddies securely but still be able to move things around easily if you change your mind or get bored. Other than that, I don't see a reason why you couldn't install more permanent second levels, if that's what you wanted.Angela.Shylah wrote: Is there reason i cqnt use aquariumn sealant directly on a plqtform for ansecond level? Willcit not hold?