Hi Fred,

1. Raising the fixture will help reduce the amount of light the tanks receive. Having the ability to easily adjust this will help in other ways as well, ie access to the tank. I use normal closet shelving to accomplish this. I posted a thread on this DIY method a couple of weeks ago.

2. Many folks use 2 bulbs for the majority of the day and then all 4 for the 'noon' affect. I think you will still get good growth with this approach.

3. I have used Verilux 30w normal flourescent bulbs on my 24" deep tank and they worked well. Keep in mind that the higher light requirement plants will not do as well. You may have to adjust your expectations and the types of plants you keep.

Suggestion: You don't have to run all 4 bulbs at once. You can mix/match as appropriate.


Hope this helps.