I'm having great success with my plants, currently. I certainly don't want to fix what isn't broke. Currently have a low tech set up and dosing ferts once a week and some CO2 injection. Prior to redoing my 55 gallon I posted a few threads asking for plant selection opinions. I posted my lighting parameters and had a few posters suggesting my light, Coral Life T5HO 4 x 39w fixture, may be too much light. So half knowing and heeding their concerns, I lowered it down to 2 x 39 w bulbs. Recently, I had some concerns about my plants (not carpeting, dwarf sagittaria) and posted my concerns on PT. I'm met with some answers saying my tank is possibly low on lighting. I'm on the lower side of the light requirements because I'm not really looking for a high tech tank. However, after looking at this chart (20 inches high and light is placed 4 inches above the tank), I'm re-evaluating...and a bit confused, do I need more light or do I need to lower it even some more? More or less need a second opinion to give me peace of mind, because it's been lingering in the back of my head.