Bulb changes

[piratefish]

I am finding that 12 weeks is too long to wait to change bulbs on my SM100.

At about week 10 I am getting algae growth on some of the rocks and sand. Not much but just enough to be annoying. Anybody having this problem?

THe problem is that after I swap bulbs it takes several week to clear up the algae on the sand and rocks.

I think I will try to swap bulbs every 10 weeks

[SantaMonica]

Sounds odd, unless that batch of bulbs was bad. If they were weak, you would see the lack of growth.