I am about to purchase your 8″ model. I have read somewhere that the life span of the bulb is only 14-18 months. If this is true, how much are the replacements? Please tell me all about the maintenance of the bulbs and anything that might need changing.
The total life of the lamp (depending on the manufacturing quality and all in use conditions being optimal) is about 18 months of continuous use (to know more, click here for the video). Understand that an old Ultra Violet lamp is much like an old MH lamp – the light may be on, but its growing potential has long since perished. From about the 12th month the ozone output begins to decrease until the 18th month and then you probably will smell very little ozone. It is best to err on the side of caution when replacing the bulbs. Therefore our recommendation is usually 14 to 18 months for replacement.
With the 8 inch BIG BLUE you have 3 bulbs. Unless you’ve undersized for the application, it is unlikely you will have all bulbs working all the same time. In other words you may only have one bulb burning for the first quarter of the growth cycle and then add lamps as the growth and odor increase. Therefore, you would not have to replace all the bulbs at the same time. If you are very serious about your garden maintenance you could date the times for each lamp and buy replacements as needed. The replacement cost as of 03/20 is approximately $50 per lamp. As for maintenance at the end of each grow cycle, it might be prudent to clean the inside reflective surfaces of your BIG BLUE. The polished surface almost doubles the effectiveness of the UV lamps. Also wipe down the bulbs as dust, oils, and fingerprints can negatively affect their performance.