i have a 55 gal with a canopy on the top and also have a glass cover over the tank under the canopy.i have recently started to have problems controling the tempurature so i installed a fan under the canopy.it helped a little but not as much as i had hoped.can i remove the glass lid,or should i leave it there?i have a yellow tang,maroon clown,purple pseudo,cleaner shrimp and assorted snails and crabs.