normal flaot glass is not that much clearer, in fact, it's less clear then acrylic.  Not sure about low iron compared to acrylic but I would assume acrylic beats it.
	
	Standard 30g's shouldn't be hard to find at all, but they are not 3' but rather 30" IIRC.  I can measure my old one when I get out to the junk pile :lol: