Thanks for the fast responses! The tank is actually only 30" long, with the standard bulb being a 24". That is another area I am having problems with.
The stock bulb is a 17watts T8 8000k. I purchased a GE daylight bulb that is 20watts T12 6500k and it seemed much darker, so I changed back to the original.
I am just confused. Would the bulbs in the link work? Or is there something else I could try?