For my 125 gal, should I buy a standard hood, buy a glass hood, use plexiglass, or other? I am thinking the plexiglass may cost almost as much as a used hood, if it's thick plexiglass? I figured I would get two 3 ft by 2 ft pieces to cover the top if I went that route. Well, it would need to be not as wide to leave room in the back I suppose. (Using hanging filters for now.) I read that other people were using 3/16" plexiglass and it could start bowing. Thanks.