Did you know that if you want to grow plants and corals in your aquarium you should replace your light tubes regularly? This is because the intensity and spectrum produced by the gasses in the bulb fade and change over time.

For best results you should replace:

Fluorescent globes every 9 months
Power compact and T5 every 12 months
Metal halide every 18 months.
UV-C globes every 18month.

It is a good idea to record when you buy the tubes in your logbook so you know when to replace them.

If you buy your lights from Majestic Aquariums you should be able to reference the purchase date on your club number on the shop computer.