Paul wrote:

For those of you that use AH lights, at what interval are you replacing the
lights? I believe the website states 12 - 14 months. I have had my 96 watt a
little over a year, Is it really time? I haven't noticed a slow down of
plant growth however am getting some fine dark green algae growing in
amongst the fine leaf plants. The tank is a 46 g Bow front w/o co2. Thanks.

Using a photographic light meter as a CRUDE gauge of light output, I have not
seen a significant drop-off after 14 months. I am confident that I can measure
an output drop in the range of 10% or more.